RESUMO
Silicon alloys have the highest specific capacity when used as anode material for lithium-ion batteries; however, the drastic volume change inherent in their use causes formidable challenges toward achieving stable cycling performance. Large quantities of binders and conductive additives are typically necessary to maintain good cell performance. In this report, only 2% (by weight) functional conductive polymer binder without any conductive additives was successfully used with a micron-size silicon monoxide (SiO) anode material, demonstrating stable and high gravimetric capacity (>1000 mAh/g) for â¼500 cycles and more than 90% capacity retention. Prelithiation of this anode using stabilized lithium metal powder (SLMP) improves the first cycle Coulombic efficiency of a SiO/NMC full cell from â¼48% to â¼90%. The combination enables good capacity retention of more than 80% after 100 cycles at C/3 in a lithium-ion full cell.
RESUMO
High capacity and high density functional conductive polymer binder/SiO electrodes are fabricated and calendered to various porosities. The effect of calendering is investigated in the reduction of thickness and porosity, as well as the increase of density. SiO particle size remains unchanged after calendering. When compressed to an appropriate density, an improved cycling performance and increased energy density are shown compared to the uncalendered electrode and overcalendered electrode. The calendered electrode has a high-density of â¼1.2 g/cm(3). A high loading electrode with an areal capacity of â¼3.5 mAh/cm(2) at a C/10 rate is achieved using functional conductive polymer binder and simple and effective calendering method.