To determine the changes of average oxidation state and cordination environment of tranisition metal ions in intercalation-based cathode mat

The increasing use of Lithium-ion batteries (LIBs) has led and will further lead to the depletion of lithium reserves. In response, investigations are being done on other cations (Na+) and anions (F-, Cl-) as shuttling ions for battery systems. Recently, fluoride ion batteries (FIBs) are considered as an alternative for all-solid-state batteries based on intercalation-based cathode materials. This has not only led to higher cycling stability but also facilitates the lowering of overpotentials. In this respect, different second-generation intercalation materials have been studied, among which La2Ni0.75Co0.25O4 and La1.9Sr0.1Ni0.9Mn0.1Co0.1O4 have been identified for improved cycling performance. Further, X-ray absorption spectroscopy has proven successful to obtain element-specific information. As it also indicates structural changes which give information on the strain-induced locally, the behavior of all transition metal cations in the pristine, charged and discharged state.

锂离子电池（LIBs）的应用规模持续扩大，不仅已然导致锂储量的消耗，且还将进一步加剧锂资源的枯竭。为此，研究人员正针对可作为电池体系穿梭离子的其他阳离子（Na+）与阴离子（F-、Cl-）开展相关研究。近年来，氟离子电池（FIBs）被视作基于插层型正极材料的全固态电池的替代方案。此类电池不仅具备更出色的循环稳定性，还可有效降低过电位。在此研究方向下，各类第二代插层材料已得到广泛探究，其中La₂Ni₀.₇₅Co₀.₂₅O₄与La₁.₉Sr₀.₁Ni₀.₉Mn₀.₁Co₀.₁O₄已被证实可改善循环性能。此外，X射线吸收光谱已被成功用于获取元素特异性信息，其不仅可反映结构变化，从而揭示局部诱导应变的相关信息，还可阐明原始、充电与放电状态下所有过渡金属阳离子的行为特性。