Expandable crosslinked polymer coatings on silicon nanoparticle anode toward high-rate and long-cycle-life lithium-ion battery
발표자
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초록
내용
Porous and electrically conductive coating on silicon nanoparticles (Si NPs) anode can mitigate the volume expansion during charging or discharging in Li-ion battery (LIB) while conventional protection coating process resulted in non-uniform polymer shell which show low volumetric or areal capacities. Here, we demonstrated that ultra-thin polyacrylonitrile layer can be formed conformally by emulsion-assisted coating process and cross-linked on Si NPs (Si@x-PAN) producing stable and expandable polymer shell which showed a highly stable long-term cycling ability. Areal and specific capacities of Si@x-PAN were an ~ 2 mAh/cm2 and a 2000 mAh/g, respectively. Importantly, we found that capacity decay was only 5 % after 100 cycles and more than 75 % of capacity was retained even after 1000 cycles (0.5C/0.5C) with the help of a uniform Li-ion current around the Si NPs during continuous charging and discharging.