Deep sodium extraction/insertion of sodium cathodes usually causes undesired Jahn–Teller distortion and phase transition, both of which will reduce structural stability and lead to poor long‐cycle reliability. Here we report a zero‐strain P2‐ Na2/3Li1/6Co1/6Mn2/3O2cathode, in which the lithium/cobalt substitution contributes to reinforcing the host structure by reducing the Mn3+/Mn4+redox, mitigating the Jahn–Teller distortion, and minimizing the lattice change. 94.5 % of Na+in the unit structure can be reversibly cycled with a charge cut‐off voltage of 4.5 V (vs. Na+/Na). Impressively, a solid‐solution reaction without phase transitions is realized upon deep sodium (de)intercalation, which poses a minimal volume deviation of 0.53 %. It attains a high discharge capacity of 178 mAh g−1, a high energy density of 534 Wh kg−1, and excellent capacity retention of 95.8 % at 1 C after 250 cycles.
This content will become publicly available on May 3, 2024
Deep sodium extraction/insertion of sodium cathodes usually causes undesired Jahn–Teller distortion and phase transition, both of which will reduce structural stability and lead to poor long‐cycle reliability. Here we report a zero‐strain P2‐ Na2/3Li1/6Co1/6Mn2/3O2cathode, in which the lithium/cobalt substitution contributes to reinforcing the host structure by reducing the Mn3+/Mn4+redox, mitigating the Jahn–Teller distortion, and minimizing the lattice change. 94.5 % of Na+in the unit structure can be reversibly cycled with a charge cut‐off voltage of 4.5 V (vs. Na+/Na). Impressively, a solid‐solution reaction without phase transitions is realized upon deep sodium (de)intercalation, which poses a minimal volume deviation of 0.53 %. It attains a high discharge capacity of 178 mAh g−1, a high energy density of 534 Wh kg−1, and excellent capacity retention of 95.8 % at 1 C after 250 cycles.
more » « less- NSF-PAR ID:
- 10429018
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 62
- Issue:
- 28
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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