The separator with excellent mechanical and thermal properties are highly required for lithium ion batteries (LIBs). Therefore, it is crucial to develop novel nanofibrous membranes with enhanced mechanical strength and thermal stability. In this work, the fluorinated polyimide (FPI) was synthesized and blended with polyvinylidene fluoride (PVDF) to fabricate composite nanofibrous membranes (CNMs) via electrospinning method. Benefiting from the introduction of aromatic FPI, the prepared PVDF/FPI nanofibrous membranes were endowed with enhanced mechanical strength and thermal stability. When the FPI content increased from 0 to 30 wt%, the tensile strength of composite nanofibrous membranes enhanced from 1.57 to 2.30 MPa. Moreover, there are almost no dimensional shrinkage for the CNM-30 containing 30 wt% FPI after heat treatment at 160 °C for 1 h. Furthermore, the prepared CNMs show improved electrochemical performances in comparison with neat PVDF and commercial Celgard membranes. The electrolyte uptake and ionic conductivity of the CNMs could reach to 522.4% and 1.14 ms•cm −1 , respectively. The prepared CNMs could provide an innovative and promising approach for the development and design of high-performance separators.

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Wearable electronic skins have aroused extensive interest in health detection, human–computer interaction, and robotics. However, it remains a great challenge to realize the multifunctional electronic skin with a wide detection range, high sensitivity, multi‐stimulus response, and wearable comfort on a single device. Here, a flexible porous thermoplastic polyurethane (TPU)/carbon black (CB) multimodal sensor that perceives multiple stimuli of pressure, strain, and humidity is prepared by the water vapor‐induced phase separation method. The as‐prepared device exhibits a wide pressure detection range (up to 49 kPa), excellent sensitivity (0.21 kPa−1), fast response (150 ms), and recovery time (120 ms). Furthermore, as a strain sensor, it is not only highly stretchable (730%), but also can operate over a strain range of 0–240% with a sensitivity of up to 1485.2 and excellent durability. Moreover, the designed sensor can detect humidity changes from 35% to 90% and has a fast response time (1.2 s), while enabling non‐contact sensing of a fingertip. Importantly, the porous TPU/CB film presents excellent breathability, enabling it to achieve a high level of comfort. Therefore, the perfect integration of these features ensures the potential applications of porous TPU/CB sensors in human activity detection, exhale monitoring, and breathable wearable devices.