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In the production of commercial Li-ion batteries, the active materials slurries are generally prepared using polyvinylidene fluoride (PVdF) as binder because of its good adhesion properties and electrochemical stability. Unfortunately, there are some disadvantages related to the use of PVdF: the most important is the use of toxic and environmentally unfriendly solvents, such as N-methyl-pyrrolidone (NMP), and the second is the high costs. In the light of these considerations, it seemed straightforward to investigate the suitability of some water-soluble, inexpensive, and eco-friendly materials to test as alternative binders (sodium alginate, chitosan tragacanth gum, gelatin). The rheological properties of these materials have been investigated in addition to the electrochemical characterization. Furthermore, graphite electrodes with PVdF, carboxymethyl cellulose (CMC), and styrene-butadiene rubber (SBR) binders have been considered for sake of comparison. We found that some of these water-soluble binders, besides good electrochemical performances, showed a high adhesion to the current collector and a good electrochemical stability under the experimental conditions employed, which makes them interesting for the next generation of Li-ion batteries. [ABSTRACT FROM AUTHOR]

A novel methacrylic gel-polymer membrane was synthesized by free radical photo polymerisation (UV-curing technique). The polymerisation was very easy, fast and reliable and the membrane shows good behaviour in terms of both conductivity and cyclability in Li cells. The anode materials were prepared by high energy ball milling obtaining nanocrystalline Ni–Sn alloys, while the hydrothermal processing in presence of a template was used to prepare nanostructured LiFePO4/C as cathode material. Every component has been characterised separately from the structural and electrochemical point of view. The first experimental data on the performance of a complete Li-ion polymer cell assembled with the components studied are also presented. The results obtained demonstrate the overall satisfying, and some superior performances of the various single components and their feasibility as a complete system. [ABSTRACT FROM AUTHOR]

The article New eco-friendly low-cost binders for Li-ion anodes, written by D. Versaci, R. Nasi, U. Zubair, J. Amici, M. Sgroi, M. A. Dumitrescu, C. Francia, S. Bodoardo and N. Penazzi, was originally published electronically on the publisher's internet portal (currently SpringerLink). [ABSTRACT FROM AUTHOR]

Highlights: [•] Mesoporous TiO2 nanocrystalline lithium battery anodes with tunable morphology. [•] Simple sol–gel technique using different cationic surfactants is adopted. [•] Textural/morphological characteristics define the electrochemical behaviour. [•] TiO2 anatase using C16TAB exhibits stable performance after 200 cycles. [•] It shows promising prospects as high-voltage safe Li-ion battery anode. [Copyright &y& Elsevier]

Abstract: Mesoporous TiO2 nanocrystals were prepared by a simple and fast hydrolytic process, in the presence of tetrabutylammonium bromide surfactant, and their ambient temperature electrochemical behaviour as high-rate Li-ion battery anodes was successfully demonstrated even after very long-term cycling (>1000 cycles). Samples were thoroughly characterized by X-ray diffraction, transmission electron microscopy, nitrogen physisorption analyses and electrochemical techniques. Using a novel synthesis approach, regular mesoporous TiO2 anatase phase with a specific surface area of 258m2 g−1 and a good degree of crystallinity was directly obtained without further treatments. The material was also calcined at different temperatures between 250 and 550°C, to increase the degree of crystallization and assess the influence of the structural modifications on the electrochemical characteristics. Very good rate capability and excellent stability upon very prolonged cycling were achieved, thus indicating the prospects of the prepared materials for next-generation high-power lithium-based batteries. [Copyright &y& Elsevier]