Stretchable conductive hydrogels with simultaneous high mechanical strength/modulus, and ultrahigh, stable electrical conductivity are ideal for applications in soft robots, artificial skin, and bioelectronics, but to date, they are still very challenging to fabricate. Herein, sandwich‐structured hybrid hydrogels based on layers of aramid nanofibers (ANFs) reinforced polyvinyl alcohol (PVA) hydrogels and a layer of silver nanowires (AgNWs)/PVA are fabricated by electrospinning combined with vacuum‐assisted filtration. The hybrid ANF‐PVA hydrogels exhibit excellent mechanical properties with the tensile modulus of 10.7–15.4 MPa, tensile strength of 3.3–5.5 MPa, and fracture energy up to 5.7 kJ m−2, primarily attributed to the strong hydrogen bonding interactions between PVA and ANFs and in‐plane alignment of the fibrous structure. Rational design of heterogeneous structure endows the hydrogels with ultrahigh apparent electrical conductivity of 1.66 × 104 S m−1, among the highest electrical conductivities ever reported so far for conductive hydrogels. More importantly, this ultrahigh conductivity remains constant upon a broad range of applied strains from 0–90% and over 500 stretching cycles. Furthermore, the hydrogels exhibit excellent Joule heating and electromagnetic interference shielding performances due to the ultrahigh electrical conductivity. These mechanically strong, hybrid hydrogels with ultrahigh and strain‐invariant electrical conductivity represent great promises for many important applications such as flexible electronics.

Conductive hydrogels as promising material candidates for soft electronics have been rapidly developed in recent years. However, the low ionic conductivity, limited mechanical properties, and insufficient freeze‐resistance greatly limit their applications for flexible and wearable electronics. Herein, aramid nanofiber (ANF)‐reinforced poly(vinyl alcohol) (PVA) organohydrogels containing dimethyl sulfoxide (DMSO)/H2O mixed solvents with outstanding freeze‐resistance are fabricated through solution casting and 3D printing methods. The organohydrogels show both high tensile strength and toughness due to the synergistic effect of ANFs and DMSO in the system, which promotes PVA crystallization and intermolecular hydrogen bonding interactions between PVA molecules as well as ANFs and PVA, confirmed by a suite of characterization and molecular dynamics simulations. The organohydrogels also exhibit ultrahigh ionic conductivity, ranging from 1.1 to 34.3 S m−1 at −50 to 60 °C. Building on these excellent material properties, the organohydrogel‐based strain sensors and solid‐state zinc–air batteries (ZABs) are fabricated, which have a broad working temperature range. Particularly, the ZABs not only exhibit high specific capacity (262 mAh g−1) with ultra‐long cycling life (355 cycles, 118 h) even at −30 °C, but also can work properly under various deformation states, manifesting their great potential applications in soft robotics and wearable electronics.

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