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Summary New applications and emerging markets in electromobility and large‐scale stationary energy storage require the development of new electrochemical systems with higher energy density than current batteries. Rechargeable metal–air batteries, mainly lithium–air and zinc–air systems, are considered one of the most promising candidates. In contrast to lithium, zinc is abundant, inexpensive and its electrodeposition in aqueous electrolytes is relatively easy. Unfortunately, achieving a rechargeable zinc–air battery is still hindered by various technical problems related to the reversibility and lifetime of the electrodes. The most widely used electrolyte in zinc–air batteries has been the classical aqueous alkaline. In this context and with the main objective of providing a complete overview, we studied a wide number of articles starting from the beginning of the development of secondary zinc–air batteries (1970–1980s) to more recent works, with the aim of compiling all available information. It is essential to revise older papers to find relevant information that may get otherwise forgotten and not taken into account to develop new solutions. This information could also be applied in other storage systems based on zinc as nickel–zinc, zinc hybrid or zinc‐ion. Copyright © 2016 John Wiley & Sons, Ltd.

Lithium-sulfur batteries are among the most promising next-generation battery systems due to the high capacity of sulfur as cathodic material. Beyond its interesting intrinsic properties, sulfur possesses a very low conductivity and complex electrochemistry, which involves the high solubility of the lithium sulfides in the electrolyte. These two characteristics are at the core of a series of limitations of its performance as active cathode material, which leads to batteries with low cyclability. Recently, inverse vulcanized sulfur was shown to retain capacity far better than elemental sulfur, leading to batteries with excellent cyclability. Nevertheless, the diene co-monomers used so far in the inverse vulcanization process are man-made molecules. Herein, a tentative work on exploring inverse vulcanization using two naturally available monomers, diallyl sulfide and myrcene, is presented. The inverse vulcanization of sulfur was successfully completed, and the resulting polymers were characterized by FTIR, NMR spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. Afterwards these polymers were tested as cathodic materials in lithium-sulfur cells. The sulfur-natural dienes materials exhibited high capacity at different C rates and high lifetime over 200 cycles with very high capacity retention at a moderate C rate of C/5. Altogether, these materials made from inexpensive and abundant chemicals are an excellent option as sustainable materials for electrochemical energy storage.

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Redox polymers with high energy storage capacity are searched in order to diminish the weight to the actual batteries. Poly­(anthraquinonyl sulfide) PAQS is a popular redox polymer which has shown a high performance cathode for lithium, sodium and magnesium batteries. Although PAQS cathodes show high cycling stability it has a relatively low theoretical specific capacity of 225 mAh/g. In this paper we show the synthesis and characterization of new poly­(anthraquinonyl sulfides) PAQxS in an attempt to improve the specific capacity of PAQS. Thus, a series of PAQxS polymers with different polysulfide segment lengths (x between 2 and 9 sulfur atoms) have been synthesized in high yields by reacting in situ formed sodium polysulfides with 1,5-dicholoroanthraquinone. The poly­(anthraquinonyl sulfides) powders were characterized by ATR-FTIR, solid state 13C NMR for the organic part and Raman spectroscopy for the chalcogenide part. This characterization confirmed the chemical structure of the PAQxS based on an anthraquinone moiety bind together by polysulfide segments. The electrochemical characterization showed a dual reversible redox mechanism associated with both the anthraquinone and polysulfide electrochemistry. Finally, lithium coin cell battery test of the PAQxS redox polymers as cathodes indicated that the capacity of poly­(anthraquinonyl sulfides) showed very high experimental initial capacity values above 600 mAh/g, less capacity loss than sulfur cathodes, and higher steady state capacity than PAQS.

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prototypes comprising ultrathin AZ31 Mg alloy anodes ( � 25 μm thick) and Mg x Mo 6 S 8 Chevrel-phase cathodes exhibited cycling performance equal to that of similar cells containing thicker pure Mg foil anodes. The possibility of using ultrathin processable Mg metal anodes is an important step in the realization of rechargeable Mg batteries.

Sulfur-containing polymers and poly(ionic liquid)s are emerging macromolecules with unique properties and applications. This article shows the first integration of these two polymer families, leading to materials with a unique combination of properties. The synthetic strategy toward sulfur-containing poly(ionic liquid)s involves first the copolymerization of elemental sulfur with 4-vinylbenzyl chloride and subsequent quaternization of the alkyl chloride group using N-methyl imidazole. The synthetic pathway is completed by the anion exchange reaction of the poly(sulfur-co-4-vinylbenzyl imidazolium chloride) by a sulphonamide anion. The obtained polymers are fully characterized by NMR, FTIR, SEC, DSC, and TGA. The sulfur poly(ionic liquid)s combine some properties related to its poly(ionic liquid) nature, such as anion-dependent solubility (water vs organic solvents) and high ionic conductivity as well as properties related to its sulfur content, such as redox activity.