The stability research of the embedding carbon layer on Si/Ge composite electrode of lithium-ion batteries

Three interstratified construction of the Si/Ge/C, Si/C/Ge and Si/C/Ge/C located on the Cu foil is demonstrated by the controlled magnetron sputtering method, and the thickness of the Si layer, Ge layer and C layer is about 75, 27 nm and 20 nm, respectively. Furthermore, the morphology of the designed stratified structure is characterized by field emission electron microscopy and its structural characterization is performed by X-ray diffraction and X-ray photoelectron spectroscopy. The results of the galvanostatic charge-discharge and rate performance tests show that the Si/C/Ge/C structural electrode attains a high cyclability with retention of 90% after 200 charge/discharge cycles.