Mechanical Design Principles of Conductive Gels Applied for Flexible Electronics

Abstract Reaping the benefits of the burgeoning investigation of gels in recent decades, flexible electronics based on conductive gels have been extensively explored. Gels consisting of polymer networks and solvents provide ideal platforms for fabricating flexible electronics due to their soft mechanical nature, excellent biocompatibility, water‐like environment, and ease of processing. The majority of investigations of flexible electronics primarily focus on functionalities such as sensing capability, energy density, luminance, fluctuating frequency, and so on, whereas the distinguishing feature of flexible electronics lies in its inherent deformable mechanics in comparison to metal‐ or semiconductor‐based stiff electronics. However, the comprehensive design and investigation of the mechanical properties of deformable conductive gels have not received sufficient attention to improve the overall performance of flexible electronics. A comprehensive summary is provided, listing six crucial mechanical parameters—stretchability, modulus, strength, elasticity, hysteresis, and fatigue—which exert significant influence on the functionalities of flexible electronics. This review aims to direct researchers’ attention toward the mechanical design of deformable conductive gels and presents representative strategies for their mechanical modulation.