Search

A flexible and free-collector-current of silicon-based anode is facilely prepared just by coating carbon black (CB) and silicon powders layer-by-layer. The resultant electrodes with a “sandwich” structure (CB/Si/CB) are assembled into half-cell and its electrochemical properties are tested. This type of anode exhibits excellent cycling and outstanding rate capability. The superior electrochemical performances are ascribed to both flexible CB-layers to offset the volume expansion of Si-particle. And, the CB-layer with high electric conductivity can provide efficient electron conductive pathways when Si particles react with lithium. More importantly, the CB/Si/CB electrodes without the collerctor (copper-foil) are exhibited high energy density, due to the weight proportion of copper foil is exceeded 60%. The CB/Si/CB electrode is used to assemble full-cell with the same structure as free-collector LCO/CB cathode material. It imposes the energy density of 200 Wh kg −1 , and can keep stable charging-discharging capability at various deformations of shapes. And the flexible-cell of high performance is obtained to meet diverse applications in energy storage devices. Until now, many flexible batteries are put forward by researchers, but these product is faced with the complex production-process, high-cost material, low energy-density. This CB/Si/CB structure is produced with the matching current manufacturing industry and the common raw material, and to get a full-cell of the high energy density. [ABSTRACT FROM AUTHOR]

As a novel anode material for lithium-ion batteries, Pb(NO3)2can deliver an initial discharge capacity as high as 1310.8 mAh g−1. However, its capacity retention is poor upon repeated cycles. In this work, carbon black (CB), graphene (GN) and carbon nanotube (CNT) are used as conductive additives to fabricate Pb(NO3)2/CB, Pb(NO3)2/GN and Pb(NO3)2/CNT, respectively. It is observed that CB and GN fail to form uniform three-dimensional conductive network for Pb(NO3)2. As a result, Pb(NO3)2/CB and Pb(NO3)2/GN do not show obviously improved electrochemical properties compared to bare Pb(NO3)2. For comparison, CNTs provide cross-linking conductive cages for Pb(NO3)2particles. It can be found that CNT coating can significantly enhance the electrochemical property of Pb(NO3)2. Pb(NO3)2/CNT reveals a reversible charge capacity of 495.2 mAh g−1after 45 cycles at a current density of 50mAg−1, which is much higher than that of bare Pb(NO3)2(227.4 mAh g−1), Pb(NO3)2/CB (278.0 mAh g−1), Pb(NO3)2/GN (327.2 mAh g−1). Even cycled at 200mAg−1, Pb(NO3)2/CNT can maintain a reversible lithium storage capacity of 411.7 mAh g−1. All these results suggest that Pb(NO3)2/CNT is a promising anode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]