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Co-free Li-rich layered oxides are gaining interest as feasible positive electrode materials in lithium-ion batteries (LIBs) in terms of energy density, cost reduction, and alleviating safety concerns. Unfortunately, their commercialization is hindered by severe structural degradation that occurs during electrochemical operation. The study at hand demonstrates advanced structural engineering of a Li-rich Co-free oxide with composition Li1.1Ni0.35Mn0.55O2by spray pyrolysis and subsequent calcination of an aqueous precursor, creating a segregated structure of two distinct layered phases with space groups R3̅m(rhombohedral) and C2/m(monoclinic). This particular structure was investigated with powder neutron diffraction, high-resolution analytical transmission electron microscopy imaging, and electron energy loss spectroscopic characterization. This complex structure contributes to the high electrochemical stability and good rate capability observed for this compound (160 mAh/g at C/3 and 100 mAh/g at 1C).These results provide new insights into the feasibility of developing and commercializing cobalt-free positive electrode materials for LIBs.

This study investigates the innovative use of a deposition technique, spray coating, for the fabrication of optimal thicknesses of solid oxide cell (SOC) layers on a range of SOC-compatible materials. The work has been carried out as part of the European KEROGREEN project that aims to utilize CO2into sustainable aircraft kerosene. To separate the oxygen at higher operating temperatures after CO2dissociation (plasmolysis) for creating a CO stream for Fischer–Tropsch downstream synthesis, a solid oxide electrolyzer cell is used. For the electrodes, the most promising LaSr-based perovskite materials were selected based on their electrical conductivity and ability to suppress the CO to CO2back reaction at the CO2(plasma) splitting side. The spray-coating suspension was adjusted to improve the adhesion and quality of the adjacent SOC layers. The electrode coatings showed good adhesion to the yttria-stabilized zirconia electrolyte, with a thickness of 10–15 µm and porosity of circa 45%. Prior to the electrodes, thin and dense interlayers were spray coated to prevent reactions between the electrolyte and the electrodes. These interlayers reduced the total electrodes resistance of the SOEC. The LaSr-based CO2electrode powder and spray-coated SOEC remained stable in the CO2/CO/O2environment.