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Hydrogel electrolytes have spurred the development of flexible energy storage devices by endowing them with liquid‐like ion transport and solid‐like mechanical elasticity. However, traditional hydrogel electrolytes always lose these functions in climate change because the internal water undergoes freezing and/or dehydration. In this work, a flexible supercapacitor (OHEC) is assembled based on the organohydrogel electrolyte (OHE) and activated carbon electrode material. The OHE is composed of PAMPS/PAAm double‐network hydrogel soaked from 4 m LiCl/ethylene glycol and exhibits good conductivities (1.9 and 22.9 mS cm−1 at −20 and 25 °C, respectively). The OHEC exhibits broad temperature adaptability (from −20 to 80 °C) and extraordinary resistance to mechanical damage (above 100 kg crushing). The OHEC avoids the polarization at low temperatures and retains 77.8% capacitance retention after storage at −20 °C for 30 days. Without extra sealed packaging, the OHEC maintains remarkable cycling stability (only 8.7% capacitance decay after 10 000 cycles) and retains 77.3% capacitance at 80 °C after 56 h. The outstanding anti‐drying performance and improved interfacial compatibility of OHEC account for the good durability in the high‐temperature environments. Additionally, other salts (such as LiClO4, NaCl, and KCl) with favorable solubility in ethylene glycol can also serve in OHEs for wide temperature range supercapacitors. [ABSTRACT FROM AUTHOR]

Though the use of conventional self‐assembled architectures in functional applications involving advanced energy chemistries is an important research area, it remains largely unexplored. The self‐assembly of the threefold and sixfold‐symmetric terpyridines (tpy) with Co(II) salts results in a novel morphological and structural characteristics, regardless of the nature of the self‐assembled fragments. Herein, such metallopolymers are achieved by one‐pot synthesis in CH3OH/CHCl3 (v/v = 5:1) mixture ambient. It is found, for the first time, that Co‐containing polymers can be well dispersed in deionized water to form gel‐like self‐assemblies that consist of a highly interconnected 3D network and exhibit enhanced electrical conductivity and thus are attractive as electrocatalysts. As expected, the optimized Co‐based polymeric structures exhibit a low overpotential of 320 mV at 10 mA cm−2 and high stability over 2000 cycles toward oxygen evolution reaction (OER), surpassing commercial RuO2/C, single‐site Co catalysts, polymer, and metal–organic framework‐based OER catalysts reported to date. X‐ray absorption spectroscopy and density functional theory calculations reveal that the tpy‐Co2+ (3N‐Co or tpy‐Co2+) configurations act as highly active sites. Importantly, this work demonstrates the functional application of the self‐assembled metallopolymers as electrocatalysts for energy conversion. [ABSTRACT FROM AUTHOR]