Samples and preparation
What a beam-time sample of these cathodes must be, and what has to happen at home before February 2027 (P0). Ni-rich surfaces change in air within days; every number refined at the facility will be compared with a number measured at home on the same powder.
Which samples
- K9: NCA, 10 % Mn–NCA, NMA, Fe/Sb–NCA, Fe/Sb–NMA, Mg–, Y–, La– and Na–NMA, as stored, and re-calcined under O₂ where possible; 2–3 g each for D2B, 0.1 g for capillaries and XAS.
- A12: the remaining 5 % Mn–NCA, Sc–NMA and the \(\mathrm{LiNbO_{3}}\)-coated NMA, for the synchrotron survey and XAS.
- Cycled electrodes: NMA, Y–, La– and Fe/Sb–NMA after 200 cycles, opened in the glove box, scraped, pooled.
- Cells for operando: the facilities' standard cells, assembled with their staff.
- References for XANES: NiO, a Ni\(^{3}\)⁺ reference (\(\mathrm{LiNiO_{2}}\) or commercial NCA), \(\mathrm{MnO_{2}}\), \(\mathrm{Li_{2}MnO_{3}}\), \(\mathrm{Fe_{2}O_{3}}\), \(\mathrm{Sb_{2}O_{3}}\), \(\mathrm{Sb_{2}O_{5}}\), \(\mathrm{Y_{2}O_{3}}\), \(\mathrm{La_{2}O_{3}}\), \(\mathrm{Sc_{2}O_{3}}\), \(\mathrm{LiNbO_{3}}\).
Measured at home, on the same powders
| ICP-OES, Li and metals, washed and unwashed |
the bulk composition every occupancy is refined under |
F01, F02, P1 |
| Titration of surface LiOH and \(\mathrm{Li_{2}CO_{3}}\); TGA–MS |
the surface lithium, separated from the bulk |
F02, F08 |
| XPS Ni 2p, Sb 3d; ⁵⁷Fe Mössbauer where available |
surface valences; the bulk Fe valence and site |
F03, F05 |
| Laboratory XRD with an internal Si standard |
the cell with zero shift stated; the two NMA cells reconciled |
F07 |
Handling
- Argon from the last calcination to the beam; vanadium cans and capillaries loaded under argon; time in air recorded.
- Natural lithium for the first round.