6 research outputs found
Lithium Manganese Sulfates as a New Class of Supercapattery Materials at Elevated Temperatures
To make supercapattery devices feasible, there is an urgent need to find electrode materials that exhibit a hybrid mechanism of energy storage. Herein, we provide a first report on the capability of lithium manganese sulfates to be used as supercapattery materials at elevated temperatures. Two compositions are studied: monoclinic LiMn(SO) and orthorhombic LiMn(SO), which are prepared by a freeze-drying method followed by heat treatment at 500 °C. The electrochemical performance of sulfate electrodes is evaluated in lithium-ion cells using two types of electrolytes: conventional carbonate-based electrolytes and ionic liquid IL ones. The electrochemical measurements are carried out in the temperature range of 20–60 °C. The stability of sulfate electrodes after cycling is monitored by in-situ Raman spectroscopy and ex-situ XRD and TEM analysis. It is found that sulfate salts store Li+ by a hybrid mechanism that depends on the kind of electrolyte used and the recording temperature. LiMn(SO) outperforms LiMn(SO) and displays excellent electrochemical properties at elevated temperatures: at 60 °C, the energy density reaches 280 Wh/kg at a power density of 11,000 W/kg. During cell cycling, there is a transformation of the Li-rich salt, LiMn(SO), into a defective Li-poor one, LiMn(SO), which appears to be responsible for the improved storage properties. The data reveals that LiMn(SO) is a prospective candidate for supercapacitor electrode materials at elevated temperatures
INFRAWEBS semantic web service development on the base of knowledge management layer
The paper gives an overview about the ongoing FP6-IST INFRAWEBS project and describes the main
layers and software components embedded in an application oriented realisation framework. An important part of
INFRAWEBS is a Semantic Web Unit (SWU) – a collaboration platform and interoperable middleware for
ontology-based handling and maintaining of SWS. The framework provides knowledge about a specific domain
and relies on ontologies to structure and exchange this knowledge to semantic service development modules.
INFRAWEBS Designer and Composer are sub-modules of SWU responsible for creating Semantic Web Services
using Case-Based Reasoning approach. The Service Access Middleware (SAM) is responsible for building up the
communication channels between users and various other modules. It serves as a generic middleware for
deployment of Semantic Web Services. This software toolset provides a development framework for creating and
maintaining the full-life-cycle of Semantic Web Services with specific application support