Abstract
The lithium-rich layered oxides are one of the most attractive cathode materials for lithium-ion batteries. Here, two types of Li1.20Ni0.32Co0.004Mn0.476O2 were synthesized using Li2CO3 and LiOH as lithium sources. An electrochemical activation process occurs in Li1.2Ni0.32Co0.004Mn0.476O2 prepared from Li2CO3 (LLO-1), while no obvious activation in Li1.2Ni0.32Co0.004Mn0.476O2 prepared from LiOH (LLO-2) is observed. Via advanced scanning transmission electron microscopy (STEM), we found that Li2MnO3-like structure is rich in the surface region of LLO-2. The study provides a direct explanation for the electrochemical activation of lithium-rich materials. The sample with more LiMO2-like phase at the surface region shows a better cycling performance. It is likely that more LiMO2-like phase at the surface region could stabilize the interface and improve the cycling performance of the Li-rich cathode materials.
| Original language | English |
|---|---|
| Pages (from-to) | 388-396 |
| Number of pages | 9 |
| Journal | Progress in Natural Science: Materials International |
| Volume | 24 |
| Issue number | 4 |
| DOIs | |
| State | Published - 2014 |
| Externally published | Yes |
Keywords
- Electrochemical activation
- Lithium-rich
- STEM imaging
- Surface structure