다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Each cell of a battery stores electrical energy as chemical energy in two electrodes, a reductant (anode) and an oxidant (cathode), separated by an electrolyte that transfers the ionic component of the chemical reaction inside the cell and forces the electronic component outside the battery. The output on discharge is an external electronic current I at a voltage V for a time Δt. The chemical reaction of a rechargeable battery must be reversible on the application of a charging I and V. Critical parameters of a rechargeable battery are safety, density of energy that can be stored at a specific power input and retrieved at a specific power output, cycle and shelf life, storage efficiency, and cost of fabrication. Conventional ambient-temperature rechargeable batteries have solid electrodes and a liquid electrolyte. The positive electrode (cathode) consists of a host framework into which the mobile (working) cation is inserted reversibly over a finite solid–solution range. The solid–solution range, which is...

The Li-ion rechargeable battery: a perspective.

Li-ion battery technology has become very important in recent years as these batteries show great promise as power sources that can lead us to the electric vehicle (EV) revolution. The development of new materials for Li-ion batteries is the focus of research in prominent groups in the field of materials science throughout the world. Li-ion batteries can be considered to be the most impressive success story of modern electrochemistry in the last two decades. They power most of today's portable devices, and seem to overcome the psychological barriers against the use of such high energy density devices on a larger scale for more demanding applications, such as EV. Since this field is advancing rapidly and attracting an increasing number of researchers, it is important to provide current and timely updates of this constantly changing technology. In this review, we describe the key aspects of Li-ion batteries: the basic science behind their operation, the most relevant components, anodes, cathodes, electrolyte solutions, as well as important future directions for R&D of advanced Li-ion batteries for demanding use, such as EV and load-leveling applications.

Challenges in the development of advanced Li-ion batteries: a review

Li-ion battery materials: present and future

Lithium titanium oxide (Li4Ti5O12) spinels are promising negative electrode materials for application in energy technology. In this work, we have synthesized Li4Ti5O12 and investigated its structure, electronic properties, and electrochemical features using several analytical spectroscopy and microscopy techniques. The equally spaced lattice fringes obtained using by the high-resolution transmission electron microscopy (HRTEM) along with electron diffraction reveal that the grown Li4Ti5O12 is well crystallized in the spinel structure without any indication of crystallographic defects such as dislocations or misfits. The electronic structure determination using high-resolution X-ray photoelectron spectroscopy (XPS) coupled with compositional studies using energy dispersive X-ray spectrometry (EDS) indicate excellent chemical quality of the Li4Ti5O12. Under the optimal synthetic condition, the sample delivers a discharge capacity of 161 mAh/g at C/12. The good cyclability of Li4Ti5O12 is attributed to the small expansion (δV≈1%) of the elementary unit-cell.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S1946427400057080

Synthesis, structure, and electrochemical properties of Li 4Ti5O12

Numerous layered structured compounds are interesting materials in which lithium intercalation occurs primarily without destruction of the host lattice. In many cases a rigid band model is a useful first approximation for describing the changes in electronic properties of the host material with intercalation. We observed, nevertheless, that the rigid-band model is not applicable to all of the layered compounds. One may argue that the applicability of the rigid-band model may be taken as a test for the properties most desirable in a good intercalation material. This needs yet to be more extensively documented for their promising applications as insertion electrode in rechargeable lithium batteries. This chapter presents the applicability of the rigid-band model on intercalation compounds with a layered structure namely the transition-metal chalcogenides MX 2 (X = S, Se) and the transition-metal oxides LiMO2 (M = Co, Ni) as well.

Christian M. Julien

Papers

Synthesis, structure, and electrochemical properties of Li 4Ti5O12

Reliability of the Rigid-Band Model in Lithium Intercalation Compounds

Optical transport spectroscopy in Li intercalated TiS 2

Geriatric profile of elderly patients treated for pancreatic cancer

Ionic transport in Li x NiPS 3