Cellulose‐Based Electrolytes in Rechargeable Zn‐Battery: An Overview

Despite commercially diffused as a primary cell, zinc battery is attracting increasing interest as rechargeable system due to its low cost, safety, and environmental sustainability. Furthermore, cellulose-based ion conducting media exploiting solid, jelled, or polymer configurations are well supporting the improvement of this intriguing energy storage system. Here, an overview of recent researches on rechargeable Zn battery, often indicated as Zn-ion battery is reported, exploiting electrolytes using cellulose. It is shown that cellulose-based electrolyte may have either solid, or gel, cross-linked hydrogel, coated, biopolymer, microfibrillated, aligned, amorphous, or self-assembled configurations. In the course of the paragraphs, how the several structural, morphological, and electrochemical studies have clarified fundamental characteristics to allow their operation in battery is revealed. On the other hand, Zn-based energy storage systems are discussed, particularly focusing on Zn–MnO2, Zn–V2O5, and Zn–air as the preferred cell configurations in terms of reliability, electrochemical performances, delivered capacity, and cycling stability. Last but not the least, the review remarks that the cost of these batteries is competitive in the global energy storage market, particularly considering the raw material availability. Therefore, the work sheds light on this dated, while emerging, system of raising interest particularly for stationary storage from discontinuous renewable sources.