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It is shown that the dissolution of elemental sulfur into, and its diffusion through, the electrolyte allows cycling of lithium–sulfur batteries in which the sulfur is initially far removed and electrically insulated from the current collector. These findings help to understand why liquid electrolyte lithium–sulfur batteries can be efficiently cycled, despite the extremely insulating properties of sulfur.

In this paper we present our project on interdisciplinary evaluations of existing smart grid environments regarding (1) the technical performance of smart energy products and services, (2) end users perceptions, (3) stakeholder processes and (4) market aspects. Our evaluations are based on data and information originating from real life pilots and demonstration projects in the field of smart grids in residential areas in the Netherlands and in Austria. The so-called CESEPS project is executed in the European ERA-Net Smart Grids Plus program. CESEPS stands for Co-Evolution of Smart Energy Product and Services. Its main objective is to support the development of smart energy products and services for local smart grids that better respond to the demands and concerns of all stakeholders in terms of performance, cost, reliability, safety and robustness, sustainability and energy-efficiency, and end users' comfort. Besides comparative data analyses and user surveys, this three year project comprises simulation activities to model existing and innovative smart grid energy products to evaluate their feasibility, given the aspects above mentioned. In this paper our approach will be explained and illustrated by several examples of ongoing subtopics of research and knowledge dissemination among stakeholders in the smart grid sector.

The relationship between structure and lithium storage capacity of different titanate samples as anode materials for lithium-ion batteries is discussed. Li 4 Ti 5 O 12 , Na 2 Ti 3 O 7 and Na 2 Ti 6 O 13 were synthesized by solid-state reaction. The structure, surface and morphology of the samples were characterized by SEM, XRD and RAMAN spectroscopy. The electrochemical performance was studied by galvanostatic charge-discharge cycling, cyclic voltammetry, electrochemical impedance spectroscopy and rate capability. The lithium titanate presented the highest capacity of the three electrodes, together with the most reversible potential plateau at 1.6 V vs. Li + /Li 0 and the best response in rate capability. Apparent diffusion coefficients of Li + ions into the titanate matrices were obtained, showing the highest value for the lithium titanate compound. Between both sodium titanates, Na 2 Ti 6 O 13 presented the highest specific capacity and the best discharge retention.

In this paper, a framework is presented for the evaluation of smart grid environment which is called the three-layer model. This three-layer model comprises three specific categories, or ‘layers’, namely, the stakeholder, market and technologies layers. Each layer is defined and explored herein, using an extensive literature study regarding their key elements, their descriptions and an overview of the findings from the literature. The assumption behind this study is that a solid understanding of each of the three layers and their interrelations will help in more effective assessment of residential smart grid pilots in order to better design products and services and deploy smart grid technologies in networks. Based on our review, we conclude that, in many studies, social factors associated with smart grid pilots, such as markets, social acceptance, and end-user and stakeholder demands, are most commonly defined as uncertainties and are therefore considered separately from the technical aspects of smart grids. As such, it is recommended that, in future assessments, the stakeholder and market layers should be combined with the technologies layer so as to enhance interaction between these three layers, and to be able to better evaluate residential smart energy systems in a multidisciplinary context.