Polymer electrolytes: Structure and transport properties
Résumé
Global warming issue imposes the increase of renewable energy use in Europe by the end of 2030. However, the intermittence of renewable resources such as solar and wind requires a large scale and safer system of energy storage. Thus, one of the locks of these future systems concerns the design and development of new solid-state electrolytes 1. Several requirements need to be fulfilled for a successful candidate of polymer-based electrolytes such as high conductivity and transport number combining with excellent mechanical properties and chemical resistance. In this work, we discuss the advantages and inconveniences of different strategies to achieve high performance electrolytes. Blend of different electrolytes appears to be the simplest way to combine different properties. However, the compatibilization and micro-structuration of these blends must be optimized to obtain the desired combination of properties. A second route allows controllable microstructuration of polyelectrolytes is the synthesis of single-ion conducting block polymer 2,3 but complicated and delicate chemistry and low conductivity stay as main obstacles. Finally, an alternative promising route that received much less attention is the development of bulky salts containing macroanion with negligible mobility resulting in higher transport number 4. In all aforementioned cases, a strong relationship between structure and transport properties of polyelectrolytes was emphasized providing a handbook for polyelectrolyte design.