Qiying Zhang, Siyao Qin, Jiajun Qu, Xiaowei Wang, Zhenyuan Li, Xuewei Fu, Zhaolin Wu, Xiangyu Chen, Weifeng Zhang, Liqun Zhang, Zhonglin Wang, Jun Liu
ABSTRACT Soft ionic conductors are ideal candidates for applications in wearable electronics, soft robotics, and human‐machine interfaces. However, achieving a balance between mechanical performance and ionic conductivity remains challenging. Besides, hydrogel‐based conductors typically fail at sub‐zero temperatures. To overcome these concurrent limitations, we report a fully solid‐state ionic conducting elastomer featuring a multi‐ionic (LiTFSI/ChCl) dual‐network derived from biomass. Molecular dynamics and density functional theory simulations verify synergistic Li─O coordination and hydrogen‐bonding networks, which enable a rare combination of mechanical strength (0.877 M Pa, 587% elongation) and high ionic conductivity (3.74 × 10 −3 S·m − 1 ). The strain sensors based on the elastomers enable stable motion sensing at −20°C and Morse code anti‐counterfeiting. Moreover, the elastomer serves as a stretchable triboelectric nanogenerator. At a resistance of 1 M Ω, the power density at −30°C increases to 290% of the value measured at room temperature, demonstrating its potential as a reliable and eco‐friendly alternative to conventional batteries in low‐temperature conditions. This work provides a novel design strategy for durable, high‐performance ionic conductors, paving the way for their use in extreme environment.