Abstract
The lithiation mechanism of methylated amorphous silicon, a-Si1−x(CH3)x:H, with various methyl contents (x = 0 - 0.12) is investigated using operando attenuated total reflection Fourier transform infrared spectroscopy. As in hydrogenated amorphous silicon, a-Si:H, the first lithiation proceeds via a two-phase mechanism. The concentration of the invading Li-rich phase nonmonotonously depends on the methyl content of the active material. This behavior is tentatively explained by two distinct effects: a softening of the material due to a methyl-induced lowering of its reticulation degree and its cohesion, and the presence of nanovoids at high enough methyl content.
| Original language | English |
|---|---|
| Article number | 1702568 |
| Journal | Advanced Energy Materials |
| Volume | 8 |
| Issue number | 13 |
| DOIs | |
| Publication status | Published - 4 May 2018 |
| Externally published | Yes |
Keywords
- Li-ion batteries
- amorphous silicon
- lithiation mechanisms
- operando ATR-FTIR
- silicon anodes