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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.

Following the hypothesis of the electrochemically stimulated conformational relaxation model (ESCRM), electrochemically generated films of poly(1-methylpyrrole), polythiophene, poly(3-methylthiophene), polyaniline, and polymethylaniline were studied by potential steps in lithium perchlorate/acetonitrile solutions. All the chronoamperograms studied by influence of different compaction potentials, or different temperatures, show a maximum, indicating the presence of conformational relaxation movements of the polymeric chains as kinetic-controlling processes of the electrochemical oxidation. Magnitudes as charge consumed to compact one mole of polymeric segments during cathodic polarization, the cathodic potential where the compaction of the polymers starts, the enthalpic increment between two stationary states defined by constant overpotentials of compaction and oxidation, and the diffusion constants stated at constant anodic overpotentials were obtained in the context pointed by the model for the studied polymers. The comparative study of the magnitudes for the different polymers, including similar magnitudes for polypyrrole and polyaniline from the literature, allows a comparative view of some structural, kinetic, and thermodynamic aspects, which can be useful for designing tailored properties, or applications, of the conducting polymers.

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