Tin is a promising anode candidate for next-generation lithium-ion batteries with a high energy density, but suffers from the huge volume change (ca. 260 %) upon lithiation. To address this issue, here we report a new hierarchical tin/carbon composite in which some of the nanosized Sn particles are anchored on the tips of carbon nanotubes (CNTs) that are rooted on the exterior surfaces of micro-sized hollow carbon cubes while other Sn nanoparticles are encapsulated in hollow carbon cubes.
View Article and Find Full Text PDFSilicon, an anode material with the highest capacity for lithium-ion batteries, needs to improve its cyclic performance prior to practical applications. Here, we report on a novel design of Si/metal composite anode in which Si nanoparticles are welded onto surfaces of metal particles by forming intermetallic interphases through a rapid heat treatment. Unlike pure Si materials that gradually lose electrical contact with conductors and binders upon repeated charging and discharging cycles, Si in the new Si/metal composite can maintain the electrical contact with the current collector through the intermetallic interphases, which are inactive and do not lose physical contact with the conductors and binders, resulting in significantly improved cyclic performance.
View Article and Find Full Text PDFMultilayered Si/RGO anode nanostructures, featuring alternating Si nanoparticle (NP) and RGO layers, good mechanical stability, and high electrical conductivity, allow Si NPs to easily expand between RGO layers, thereby leading to high reversible capacity up to 2300 mAh g(-1) at 0.05 C (120 mA g(-1) ) and 87% capacity retention (up to 630 mAh g(-1) ) at 10 C after 152 cycles.
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