Seaweed extractions as promising polymer electrolytes for lithium batteries

Polymer electrodes are vital components of lithium-ion batteries and have gained great interest in recent years. Currently, the majority of electrodes are petroleum-based that are toxic and non-biodegradable, which consists of serious environmental concerns. Therefore, exploration of natural polymer electrolytes, such as seaweed extracts, balances non-toxicity and ion conductivity as new research directions. In this review, we mainly focus on the progress of polymer electrolytes based on alginate, kappa carrageenan, and other natural polymers of seaweed extracts, including agar and iota carrageenan. We first give a brief overview of the fundamentals of polymer electrolytes. Then, we discuss the structures and performances of seaweed extracts derived polymer electrolytes. Finally, we compare the ion conductivity of natural polymer derived electrolytes and synthetic polymers, and insights on the future direction for improvement of this field