Fluoride ion batteries (FIBs) are a recent alternative all-solid-state battery technology. However, the FIB systems proposed so far suffer from poor cycling performance. In this work, we report La₂NiO_4.13 with a Ruddlesden-Popper type structure as an intercalation-based active cathode material in all solid-state FIB with excellent cycling performance. The critical charging conditions to maintain the conductivity of the cell were determined, which seems to be a major obstacle towards improving the cycling stability of FIBs. For optimized operating conditions, a cycle life of about 60 cycles and over 220 cycles for critical cut-off capacities of 50 mAh/g and 30 mAh/g, respectively, could be achieved, with average Coulombic efficiencies between 95 – 99%. Cycling of the cell is a result of fluorination/de-fluorination into and from the La₂NiO_4+d cathode, and it is revealed that La₂NiO_4.13 is a multivalent electrode material. Our findings suggest that La₂NiO_4.13 is a promising high energy cathode for FIBs.

氟化物离子电池（FIB）是最近的替代性全固态电池技术。然而，迄今为止提出的FIB系统遭受不良的循环性能的困扰。在这项工作中，我们报告La ₂ NiO _4.13在所有固态FIB中具有Ruddlesden-Popper型结构作为插层型活性阴极材料，具有出色的循环性能。确定了维持电池电导率的关键充电条件，这似乎是改善FIB循环稳定性的主要障碍。对于优化的工作条件，对于50 mAh / g和30 mAh / g的临界截断容量，可以实现约60个循环和超过220个循环的循环寿命，平均库仑效率在95 – 99％之间。电池的循环是向/从La ₂ NiO _{4 + d}阴极氟化/脱氟化的结果，结果表明La ₂ NiO _4.13是一种多价电极材料。我们的发现表明，La ₂ NiO _4.13是有前途的FIB高能阴极。