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Poly(m-phenylene isophthalamide) (PMIA) membranes are promising heat-tolerant separator candidates of lithium-ion batteries (LIBs), while their wettability toward carbonate electrolyte and corresponding batteries performance are not desirable. Herein, PMIA membranes coated with ultrathin mussel-inspired polydopamine (PDA) layer were fabricated as separators in LIBs. The introduced amino, quinonyl, and catechol groups in PDA coating could enhance the wettability of the resultant PMIA-PDA separator toward electrolyte. The PMIA-PDA separator had excellent thermal stability, showing a thermal shrinkage of 5.2% at 200 °C. The contact angle of the thermal-treated PMIA-PDA separator could maintain at 26.1°, which decreased by 42.7% compared with the pristine PMIA separator. The PMIA-PDA separator also displayed a high ionic conductivity (0.86 mS cm−1) and a low interfacial electric resistance (62.4 Ω). Consequently, the assembled LiCoO2/PMIA-PDA/Li battery achieved good cyclic stability with the capacity retention of 84.3% (121.1 mAh g−1) after 100 cycles under 30 °C. More significantly, the relevant capacity retention remained at 89.0% (127.5 mAh g−1) under 60 °C, which implied a great potential of PMIA-PDA membranes as separators of high-safety LIBs. [ABSTRACT FROM AUTHOR]

The effect of colemanite additives on sintering and the properties and microstructure of spodumene ceramic is studied. It is found that to identify the sintering and formation processes of a higher-density structure of ceramic it is most effective to introduce colemanite in the amounts 5 - 7%. Spodumene ceramic with CLTE (9.8 - 12.9) × 10 K, heat-tolerance greater than 100 heat cycles (800°C - water), water absorption 0.7 - 5.0%, and mechanical strength under bending 33 - 44 MPa, which all obtain at the sintering temperature 1200°C, was obtained. [ABSTRACT FROM AUTHOR]