Recent progress and perspectives on advanced flexible Zn-based batteries with hydrogel electrolytes

Abstract

Hydrogel electrolytes, which feature intriguing characteristics of being soft and wet, accompanied with high solubility of zinc salts, are especially advantageous for fabricating flexible Zn-based batteries. Furthermore, the abundant and tunable chemistries of hydrogels offer opportunities to bestow novel affiliated functionalities, such as super toughness, extreme temperature tolerance, stimuli-responsive properties, and self-healing capability, by engineering polymer chains and chemical structures to fabricate flexible batteries with unprecedentedly scintillating functions. Herein, the design principles of functional hydrogel electrolytes including polymer chemistry, synthesis methods, characterisation and versatility demonstration for flexible Zn-based batteries are comprehensively reviewed. Relevant challenges and perspectives are also analysed and discussed.