Proton Conducting Membranes Based on Poly(Ionic Liquids) Having Phosphonium Counter-Cations.

Proton conducting polymeric membranes are highly searched in many different technologies ranging from energy to biosensing. Protic ionic liquids and their polymeric version represent a new family of proton conducting molecules with relatively facile synthesis and excellent properties. In this work, protic poly(ionic liquids) having the most popular phosphonium counter-cations are presented for the first time. The synthesis is carried out through proton transfer reactions or through ion exchange reactions by using commercially available tertiary phosphines. Tributyl-, trioctyl-, and tricyclohexyl-phosphine are selected to form the desired cations. Polystyrene sulfonic acid, poly(2-acrylamido-2-methyl-1-propanesulfonic acid), and lithium poly[(4-styrenesulfonyl) (trifluoromethanesulfonyl)imide] polymers are used to form the polymeric anions. The chemical structure of the protic poly(ionic liquids) is confirmed by spectroscopic characterizations such as Fourier transform infrared and nuclear magnetic resonance spectroscopies. Thermal properties of the polymer are characterized by means of differential scanning calorimetry and thermogravimetric analysis. Polymers exhibit good membrane forming ability as well as high ionic conductivities in the range of 10-8 to 10-3 S cm-1 from 30 to 90 °C.

All-Solid-State Lithium-Ion Batteries with Grafted Ceramic Nanoparticles Dispersed in Solid Polymer Electrolytes.

Lithium-based rechargeable batteries offer superior specific energy and power, and have enabled exponential growth in industries focused on small electronic devices. However, further increases in energy density, for example for electric transportation, face the challenge of harnessing the lithium metal as negative electrode instead of limited-capacity graphite and its heavy copper current collector. All-solid-state batteries utilize solid polymer electrolytes (SPEs) to overcome the safety issues of liquid electrolytes. We demonstrate an all-solid-state lithium-ion battery by using plasticized poly(ethylene oxide)-based SPEs comprising anions grafted or co-grafted onto ceramic nanoparticles. This new approach using grafted ceramic nanoparticles enables the development of a new generation of nanohybrid polymer electrolytes with high ionic conductivity as well as high electrochemical and mechanical stability, enabling Li-ion batteries with long cycle life.