“Seaweed Structure” design for solid gel electrolyte with hydroxide ion conductivity enabling flexible zinc air batteries

Abstract

The construction of solid-state electrolytes for flexible zinc-air batteries is extremely challenging. A flexible and highly conductive solid electrolyte designed with a “seaweed structure” is reported in this work. Sodium alginate serves as the backbone to form a robust network structure, and the grafted quaternary ammonium groups provide channels for rapid ion transport, achieving excellent flexibility and hydroxide conductivity. The conductivity of the modified electrolyte membrane (QASA) is 5.23 × 10−2 S cm−1 at room temperature and reaches up to 8.51 × 10−2 S cm−1 at 75 °C. In the QASA based battery, bending at any angle is realized, and the power density is up to 57.28 mW cm−2. This work provides a new way to prepare high conductivity, green solid-state zinc-air batteries, and opens up a research line of thought for flexible energy storage materials.