Electrodeposited porous-microspheres Li–Si films as negative electrodes in lithium-ion batteries

A porous-microspheres Li–Si film (PMLSF) is prepared by multi-step constant current (MSCC) electrodeposition on Cu foil. Its structure and morphology are characterized using X-ray diffraction (XRD) and scanning electron microscope (SEM). As negative electrodes of lithium-ion batteries, the PMLSF electrode delivers the first gravimetric and geometric charge capacities of 2805.7 mA h g−1 and 621.9 μA h cm−2 at the current density of 25.5 μA cm−2, and its initial coulombic efficiency is as high as 98.2%. When the PMLSF electrode is cycled in VC-containing electrolyte, the superior cycling performance can be obtained. After 50 cycles, 96.0% of its initial capacity is retained at the current density of 50.0 μA cm−2. Electrochemical impedance spectra (EIS) research confirms the positive effect of VC additive on the behavior of the PMLSF electrode.

The porous-microspheres Li–Si film (PMLSF) was first electrodeposited via multi-step constant current technique on Cu foil. This film was mainly composed of irregular and inter-connected porous-microspheres with different sizes ranging from several micrometers to several tens of micrometers. As negative electrodes for lithium-ion battery, the PMLSF electrode exhibited high initial coulombic efficiency and good cycling stability.Figure optionsDownload as PowerPoint slideResearch highlights▶ Li and Si are co-deposited from a non-aqueous electrolyte solution. ▶ The porous-microspheres Li–Si film is first prepared via electrodeposition. ▶ Co-deposition of Li and Si leads to a high initial coulombic efficiency (>90%). ▶ The particular film morphology favors a superior cycling stability.