In situ formed cross-linked polymer networks as dual-functional layers for high-stable lithium metal batteries

Lithium-metal anodes(LMAs)have been recognized as the ultimate anodes for next-generation batteries with high energy density,but stringent assembly-environment conditions derived from the poor moisture stability dramatically hinder the transformation of LMAs from laboratory to industry.Herein,an in situ formed cross-linked polymer layer on LMAs is designed and constructed by a facile thiol-acrylate click chemistry reaction between poly(ethylene glycol)diacrylate(PEGDA)and the crosslinker containing multi thiol groups under UV irradiation.Owing to the hydrophobic nature of the layer,the treated LMAs demonstrate remarkable humid stability for more than 3 h in ambient air(70%relative humidity).The coating humid-resistant protective layer also possesses a dual-functional characterization as solid polymer electrolytes by introducing lithium bis(trifluoromethanesulfonyl)imide in the system in advance.The intimate contact between the polymer layer and LMAs reduces interfacial resistance in the assembled Li/LiFePO_(4)or Li/LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)full cell effectively,and endows the cell with an outstanding cycle performance.

Effect of polyethylene glycol on the crystallization,rheology and foamability of poly(lactic acid)containing in situ generated polyamide 6 nanofibrils

In this study,the rheological properties,crystallization and foaming behavior of poly(lactic acid)with polyamide 6 nanofibrils were examined with polyethylene glycol as a compatibilizer.Polyamide 6 particles were deformed into nanofibrils during drawing.For the 10%polyamide 6 case,polyethylene glycol addition reduced the polyamide 6 fibril diameter from 365.53 to 254.63 nm,owing to the smaller polyamide 6 particle size and enhanced interface adhesion.Rheological experiments revealed that the viscosity and storage modulus of the composites were increased,which was associated with the three-dimensional entangled network of polyamide 6 nanofibrils.The presence of higher aspect ratio polyamide 6 nanofibrils substantially enhanced the melt strength of the composites.The isothermal crystallization kinetics results suggested that the polyamide 6 nanofibrils and polyethylene glycol had a synergistic effect on accelerating poly(lactic acid)crystallization.With the polyethylene glycol,the crystallization half-time reduced from 103.6 to 62.2 s.Batch foaming results indicated that owing to higher cell nucleation efficiency,the existence of polyamide 6 nanofibrils led to a higher cell density and lower expansion ratio.Furthermore,the poly(lactic acid)/polyamide 6 foams exhibited a higher cell density and expansion ratio than that of the foams without polyethylene glycol.