1,721,239 research outputs found
Nanocomposite lithium ion conducting membranes
This review describes the properties and characteristics of a class of membranes formed by blends of a lithium salt, LiX, where X is preferably a large soft anion, such as ClO4 or N(CF3SO2)(2), and a high molecular weight polymer containing Li+-coordinating group, such as polyethylene oxide (PEO) with the dispersion of selected ceramic powders, such as TiO2, Al2O3, and SiO2, at the nanoscale particle size. These nanocomposite membranes behave as lithium polymer electrolytes, that is, they exhibit a high lithium ion conductivity. Because of this property, the PEO-LiX nanocomposite electrolytes may rind an important application as separators in advanced, rechargeable lithium polymer batteries
Lithiated short side chain perfluorinated sulfonic ionomeric membranes: Water content and conductivity
In view of possible applications as single-ion electrolyte for lithium batteries, some aspects of the lithium form of Hyflon Ion ionomer, a sulfonic short side chain (SSC) electrolyte, have been investigated. The synthesis of the ionomer and the successive membrane preparation is reported. An appropriate methodology for the direct salification of the ionomeric membrane from the SO2F form to lithium salt, using lithium hydroxide in absence of organic solvent has been found. Utilizing these SSC lithium ionomer membranes and though a particular methodology for the dehydration of the lithium ion membrane in non-aqueous media, it has been possible to achieve an ionic conductivity of 10(-3) S cm(-1) at room temperature [W. Navarrini, S. Panero, B. Scrosati, A. Sanguineti, European Patent 1,403,958 A1 (2003)]. Surprisingly it was observed that the membrane ionic conductivity depends on the dehydration methodologies adopted. (C) 2007 Elsevier B.V. All rights reserved
High-performance electrolyte membranes for plastic lithium batteries
The synthesis, properties, and application of new types of lithium-ion conducting polymeric membranes are reported and discussed. These ionic membranes are dimensionally stable, have a very high ionic conductivity, an acceptable lithium-ion transference number and a wide electrochemical stability window. Due to these favourable properties, these membranes are suitable for the fabrication of advanced-design, high-performance batteries and power source devices
Accumulatori litio-zolfo
La presente invenzione si riferisce al settore degli accumulatori ( o batterie) al litio con configurazione elettrochimica innovativa. In particolare, l’invenzione descrive nuovi accumulatori litio-zolfo, dove l’anodo (elettrodo negativo) può essere litio metallico o un composto del tipo M-C dove M è scelto nel gruppo costituito da Sn, Sb, Si, Mg, Al o leghe tra loro, il catodo è a base di solfuro di litio, Li2S e l’elettrolita è una membrana gel a base di ossido di polietilene contenente una soluzione satura di solfuro di litio in una miscela di etilene carbonato-dimetilcarbonato.
Vantaggiosamente, la presente invenzione consente lo sviluppo di accumulatori polimerici litio-zolfo con prestazioni superiori rispetto a quelle delle attuali batterie al litio. L’innovazione consiste nella combinazione dei tre materiali costituenti l’accumulatore e, in particolare, dalla composizione del materiale elettrolitico polimerico dove l’aggiunta fino a saturazione di solfuri e/o polisolfuri di litio previene la dissoluzione del catodo conferendo stabilità operativa all’accumulatore stesso
Impedance spectroscopy study of PEG-based nanocomposite polymer electrolytes
The addition of nanometric fillers (e.g., SiO2, TiO2) to P(EO)(n)LIClO4 polymer electrolytes induces consistent improvement in the transport properties. The increase in conductivity and in the cation transference number is attributed to the enhancement of the degree of the amorphous phase in the polymer matrix, as well as to some acid-base Lewis type, ceramic-electrolyte interactions. This model is confirmed by results obtained from a detailed impedance spectroscopy study carried out on poly(ethylene oxide) [P(EO)]-based polymer electrolyte samples with and without ceramic fillers. (C) 2000 The Electrochemical Society. S0013-4651(99)10-094-6. All rights reserved
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