The high energy density required for the next generation of lithium batteries will likely be enabled by a shift toward lithium metal anode from the conventional intercalation‐based anode such as ...graphite. However, several critical challenges for Li metal originate from its highly reactive nature and the hostless reaction of deposition and stripping impede the practical use of Li metal as an anode. The role of the solid electrolyte interphase (SEI) is very important for the Li metal anode where the SEI must protect the dynamically changing surface of the Li metal. Since the SEI‐generating reaction mechanisms for the two different electrolyte systems, liquid and solid, are considerably different, the SEI layers formed between the Li metal and the electrolytes in the two electrolyte systems have substantially different properties, causing different interfacial issues. Inhibition of the interfacial problems requires different strategies to reinforce the SEI layer for each of the electrolyte systems. However, the differences in the two electrolyte systems have not been clearly compared in the prior literature. In this report, the interfacial issues for the two different electrolyte systems are compared and different strategies for SEI modification are provided to overcome the issues.
Lithium metal anodes face different interfacial issues in liquid electrolyte and solid electrolyte systems. To overcome the interfacial problems, modification strategies of solid electrolyte interphases (SEI) should be different in each system. This perspective article illuminates the interfacial issues and discusses the strategies of SEI modification in each electrolyte system.
Extensive applications of rechargeable lithium-ion batteries (LIBs) to various portable electronic devices and hybrid electric vehicles result in the increasing demand for the development of ...electrode materials with improved electrochemical performance including high energy, power density, and excellent cyclability, while maintaining low production cost. Here, we present a direct synthesis of ferrite/carbon hybrid nanosheets for high performance lithium-ion battery anodes. Uniform-sized ferrite nanocrystals and carbon materials were synthesized simultaneously through a single heating procedure using metal–oleate complex as the precursors for both ferrite and carbon. 2-D nanostructures were obtained by using sodium sulfate salt powder as a sacrificial template. The 2-D ferrite/carbon nanocomposites exhibited excellent cycling stability and rate performance derived from 2-D nanostructural characteristics. The synthetic procedure is simple, inexpensive, and scalable for mass production, and the highly ordered 2-D structure of these nanocomposites has great potential for many future applications.
A vanadium pentoxide electrode is prepared in the amorphous form (a-V2O5), and its electrode performances are compared to those for its crystalline counterpart (c-V2O5). The a-V2O5 electrode ...outperforms c-V2O5 in several ways. First, it is free from irreversible phase transitions and Li trapping, which evolve in c-V2O5, probably due to the lack of interactions between the inserted Li+ ions/electrons and V2O5 matrix. Second, the absence of Li trapping allows a reversible capacity amounting to >600 mA h g–1, which is larger than that given by c-V2O5. Third, it shows an excellent rate property. The notably high reversible capacity and rate capability seem to be due to Li storage at vacant sites that are ill-defined but numerous in a-V2O5, which Li+ ions can easily access. However, irreversible capacity of a-V2O5 is appreciable in the first cycle due to a parasitic Li reaction with surface hydroxyl groups. Treatment with n-butyllithium can suppress the irreversible capacity by removing the surface hydroxyl groups.
The corrosion behavior of aluminum foil that is used as the positive current collector for lithium-ion batteries is studied in N-methyl-N-propyl-pyrrolidinium bis(fluorosulfonyl)imide (PMPyr-FSI), ...which is considered as a highly attractive solvent due to a very low viscosity. This work reports that FSI anion is corrosive for aluminum foil upon anodic polarization (>4.0V vs. Li/Li+). The pitting corrosion is, however, greatly reduced by adding lithium hexafluorophosphate (LiPF6). The anion of the salt is known to be a corrosion inhibitor for aluminum. It likely reacts to generate hydrofluoric acid that then attacks the native aluminum oxide (Al2O3) to produce a strong passivation layer comprising aluminum fluoride (AlF3). Resultantly, the high rate capability, which is the potential merit achievable by using the FSI-containing ionic liquid solvent, can be implemented with a LiCoO2 positive electrode.
► Al positive current collector is corroded by an attack of FSI anion. ► Addition of LiPF6 leads to a formation of a strong passivation layer (AlF3). ► The absence of corrosion on the Al current collector allows a stable cycling of LiCoO2 electrode. ► A high-rate cycling is achieved by using the FSI-based ionic liquid solvent of low viscosity.
An investigation of the damping wiggler effect to reduce the emittance in the Pohang Accelerator Laboratory (PAL), a fourth‐generation storage ring (4GSR) that uses a multi‐bend achromat, is ...presented. A 4GSR lattice which has reduced emittance and increased dynamic aperture to amplify the synergy with two existing light sources (PLS‐II and PAL‐XFEL) at PAL is described.
An investigation of the damping wiggler effect to reduce the emittance in the Pohang Accelerator Laboratory (PAL), a fourth‐generation storage ring (4GSR) that uses a multi‐bend achromat, is presented.
Low emittance lattice design for Korea-4GSR Jang, G.S.; Shin, S.; Yoon, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2022, Letnik:
1034
Journal Article
Recenzirano
Odprti dostop
The lattice type of Korea 4th Generation Storage Ring (Korea-4GSR) is determined as hybrid multi-bend achromat type (HMBA) after a comparison of three types of multi-bend achromat (MBA) lattices ...because HMBA provides sufficiently low beam emittance and good nonlinear beam dynamics with the smallest number of sextupole magnets among the three types of lattices. We also propose the use of bending beamlines with 2 T centre bending magnets (CBMs). Considering the determined lattice type, longitudinal gradient bending magnets and reverse bending magnet were used to reduce the emittance and use of damping wigglers is being considered to reduce emittance further. The ring design result shows that the natural emittance of Korea-4GSR is 58 pm and can be reduced 28% by adopting damping wigglers. Linear and nonlinear dynamics aspects of Korea-4GSR including intrabeam scattering simulation is demonstrated and error effects on Korea-4GSR were also investigated.
Purpose
The da Vinci SP® (dVSP) surgical system (Intuitive Surgical, Sunnyvale, CA, USA), a robotic platform designed for single-incision surgery, overcame the need for multiple ports in traditional ...robotic surgery and issues including triangulation and retraction in single-incision laparoscopic surgery. However, previous studies only included case reports or series with small sample sizes. The aim of this study was to assess the safety and performance of the dVSP surgical system and its instruments and accessories for colorectal procedures.
Methods
The medical records of patients who had surgery with the dVSP from March 2019 to September 2021 at Ewha Womans University Seoul Hospital were investigated. The pathologic and follow-up data of patients who had malignant tumors were analyzed separately to evaluate oncological safety.
Results
Fifty patients (26 male and 24 female) with a median age of 59 years (interquartile range 52.5–63.0 years) were enrolled. The procedures included low anterior resection with total mesorectal excision (
n
= 16), sigmoid colectomy with complete mesocolic excision and central vessel ligation (CME + CVL) (
n
= 14), right colectomy with CME + CVL (
n
= 9), left colectomy with CME + CVL (
n
= 4), right colectomy (
n
= 6), and sigmoid colectomy (
n
= 1). Operative time significantly decreased after 25 cases (early phase vs. late phase; operative time 295.0 min vs. 250.0 min,
p
= 0.015; docking time 16.0 min vs. 12.0 min,
p
= 0.001; console time 212.0 min vs. 190.0 min,
p
= 0.019). Planned procedures were successfully completed in all patients. Postoperative outcomes were acceptable with only six cases of mild adverse events through a 3-month follow-up. No local recurrence and only one case of systemic recurrence occurred within 1 year postoperatively.
Conclusions
This study demonstrated the surgical and oncological safety and feasibility of dVSP, which may be a novel surgical platform for colorectal surgery.
The current commercially used anode material, graphite, has a theoretical capacity of only 372 mAh/g, leading to a relatively low energy density. Lithium (Li) metal is a promising candidate as an ...anode for enhancing energy density; however, challenges related to safety and performance arise due to Li's dendritic growth, which needs to be addressed. Owing to these critical issues in Li metal batteries, all-solid-state lithium-ion batteries (ASSLIBs) have attracted considerable interest due to their superior energy density and enhanced safety features. Among the key components of ASSLIBs, solid-state electrolytes (SSEs) play a vital role in determining their overall performance. Various types of SSEs, including sulfides, oxides, and polymers, have been extensively investigated for Li metal anodes. Sulfide SSEs have demonstrated high ion conductivity; however, dendrite formation and a limited electrochemical window hinder the commercialization of ASSLIBs due to safety concerns. Conversely, oxide SSEs exhibit a wide electrochemical window, but compatibility issues with Li metal lead to interfacial resistance problems. Polymer SSEs have the advantage of flexibility; however their limited ion conductivity poses challenges for commercialization. This review aims to provide an overview of the distinctive characteristics and inherent challenges associated with each SSE type for Li metal anodes while also proposing potential pathways for future enhancements based on prior research findings.
The Korea fourth-generation storage ring (Korea-4GSR), with 4-GeV beam energy and 58-pm-rad emittance has been designed by the Pohang Accelerator Laboratory. The evaluated brilliance and coherence ...are approximately 100 times higher in the hard X-ray region in Korea-4GSR than in the third-generation storage ring at PLS-II. The coherence properties and preservation of coherence through beamline optical elements were studied using SPECTRA code and hybrid method. Result of this paper show essential information for planning experiments and designing beamlines using ultimate low emittance storage ring.
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