Abstract
During solid-state calcination, with increasing temperature, materials undergo complex phase transitions with heterogeneous solid-state reactions and mass transport. Precise control of the calcination chemistry is therefore crucial for synthesizing state-of-the-art Ni-rich layered oxides (LiNi1-x-yCoxMnyO2, NRNCM) as cathode materials for lithium-ion batteries. Although the battery performance depends on the chemical heterogeneity during NRNCM calcination, it has not yet been elucidated. Herein, through synchrotron-based X-ray, mass spectrometry microscopy, and structural analyses, it is revealed that the temperature-dependent reaction kinetics, the diffusivity of solid-state lithium sources, and the ambient oxygen control the local chemical compositions of the reaction intermediates within a calcined particle. Additionally, it is found that the variations in the reducing power of the transition metals (i.e., Ni, Co, and Mn) determine the local structures at the nanoscale. The investigation of the reaction mechanism via imaging analysis provides valuable information for tuning the calcination chemistry and developing high-energy/power density lithium-ion batteries.
| Original language | English |
|---|---|
| Article number | 2207076 |
| Journal | Advanced Materials |
| Volume | 35 |
| Issue number | 10 |
| DOIs | |
| State | Published - Mar 9 2023 |
| Externally published | Yes |
Funding
This research was supported by the Samsung Science and Technology Foundation under project no. SRFC-MA2002-04. J.L. acknowledges the National Research Foundation of Korea (NRF, 2021R1C1C1013953, 2022K1A4A7A04094394, and 2022K1A4A7A04095890); the Korea Basic Science Institute (KBSI) under an R&D program (Ministry of Science and ICT, no. D39701) for nano-SIMS imaging; and Pohang Light Source (PLS) for the beamline support. Y.P., M.H., and K.J. acknowledge the International Collaborative Energy Technology R&D program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) under the authority of the Ministry of Trade, Industry, and Energy (MOTIE) of the Republic of Korea and the U.S. Department of Energy (DoE) (Contract No. 20198510050010). This research was also supported by the Research Institute of Advanced Materials (RIAM), the National Center for Inter-university Research Facilities (NCIRF), and the Institute of Applied Physics at Seoul National University. This research was supported by the Samsung Science and Technology Foundation under project no. SRFC‐MA2002‐04. J.L. acknowledges the National Research Foundation of Korea (NRF, 2021R1C1C1013953, 2022K1A4A7A04094394, and 2022K1A4A7A04095890); the Korea Basic Science Institute (KBSI) under an R&D program (Ministry of Science and ICT, no. D39701) for nano‐SIMS imaging; and Pohang Light Source (PLS) for the beamline support. Y.P., M.H., and K.J. acknowledge the International Collaborative Energy Technology R&D program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) under the authority of the Ministry of Trade, Industry, and Energy (MOTIE) of the Republic of Korea and the U.S. Department of Energy (DoE) (Contract No. 20198510050010). This research was also supported by the Research Institute of Advanced Materials (RIAM), the National Center for Inter‐university Research Facilities (NCIRF), and the Institute of Applied Physics at Seoul National University.
Keywords
- Li-ion batteries
- nickel-rich cathodes
- phase transitions with solid-state reaction
- spatial distribution of local chemical compositions within the particles
- synthesis during calcination
