Investigation of Alkali‐Ion (Li,Na, and K) Intercalation in KxVPO4F (x ∼ 0) Cathode |
| |
| Authors: | Haegyeom Kim Yuji Ishado Yaosen Tian Gerbrand Ceder |
| |
| Affiliation: | 1. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720 USA;2. Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga, Fukuoka, 816‐8580 Japan;3. Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720 USA;4. https://orcid.org/0000-0001-9275-3605;5. Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720 USAE‐mail: |
| |
| Abstract: | This work compares the intercalation of K, Na, and Li in KxVPO4F (x ～ 0). The KxVPO4F (x ～ 0) cathode delivers reversible capacities of ≈90–100 mAh g?1 in K, Na, and Li cells, at an average voltage of ≈4.33 V for K, ≈3.98 V for Na, and ≈3.96 V for Li. This is so far the highest average voltage known for a K‐intercalation cathode. The lower voltage of Li insertion compared to Na is attributable to undercoordinated Li ions in the KxVPO4F (x ～ 0) framework. While the material shows high rate capability for all the alkali ions, Li migration in KxVPO4F (x ～ 0) is more difficult than with Na and K. This work suggests that a large cavity is not always good for insertion of alkali ions and cathode materials need to be suitably tailored to each intercalating ion species. |
| |
| Keywords: | batteries cathodes lithium potassium sodium |
|
|
