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Safety issue is the main concern for current lithium-ion batteries (LIBs), especially for the high energy density cells based on nickel-rich oxide/Si-C chemistries, which could experience violent explosion and intense burning with the temperature exceeding 1000 °C during thermal runaway (TR). And moreover, within a module/system, the TR of a single cell might trigger the TR of neighboring cells, usually called TR propagation, leading to a fire accident or even a server disaster. The objective of this work is to introduce an aerogel sheet with extremely low thermal conductivity and high thermal stability to block the TR propagation. The silica aerogel sheet (SAS) is synthesized via a sol-gel process followed by supercritical fluid drying. The thermal conductivities of the obtained SAS are 0.018, 0.029, 0.043 and 0.074 W (m·K) −1at 20 °C, 300 °C, 500 °C and 800 °C, respectively. A simple module is constructed with two LIBs (NCM811/Si-C, 320 Wh/kg) sandwiched with a piece of SAS with various thicknesses (1.2–2.8 mm). The results show that the SAS of 1.2 mm or 1.8 mm thickness cannot stop the TR propagation. The propagation times to next cell are 50 (1.2 mm) and 106 s (1.8 mm), respectively. While the SAS of 2.3 mm or thicker can suppress the TR propagation successfully, and moreover, protect the neighboring cell from any voltage drop/collapse. The microstructure and thermal conductivity of the SAS after TR experiments do not show evident change, revealing that the as-prepared SAS is thermally stable during the violent TR process. This work provides new insights for battery thermal management system (BTMS).

Ceramic membrane separation has been widely used in industrial wastewater treatment, but membrane contamination problems have limited its efficient and economical application. This study introduced reduced graphene oxide (rGO) and carbon nanotubes (CNTs) into the preparation of polypyrrole (PPy). Both rGO and CNTs were loaded on the surface layer of a ceramic membrane by an in situoxidative polymerization-self-assembly method to form an rGO–CNT–PPy modified ceramic membrane, which was supplemented with an electric field effect to improve the antifouling performance. Characterization and electrochemical analysis indicated that the modified conductive ceramic composite membrane exhibited excellent electrical conductivity and stability, with an average square resistance of 78.9 Ω sq−1. The experimental results showed that TN, COD, NH3-N, Ni, Fe, and Cu were well removed under certain conditions with a removal efficiency of 63.60%, 64.00%, 68.31%, 89.90%, 95.04%, and 88.82%, respectively. Meanwhile, the pH of pickling wastewater increased from 2.61 to 6.63, and the membrane contamination was significantly improved. Furthermore, after 5 runs, the decay of membrane flux was less than 12%, and this modified conductive ceramic composite membrane was subjected to an electric field, which can effectively slow down the membrane contamination phenomenon. This approach based on the rGO–CNT–PPy modified conductive ceramic membrane provides a clean and effective technique for membrane contamination control.