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[en] Highlights: • Importance of mixing intensity for aqueous LiFePO4 cathode slurries is demonstrated. • Fe3+ rich layer formation on intensively mixed LiFePO4 electrode surface is detected. • C/LiFePO4 pouch cells with aqueous processed electrodes show outstanding cyclability. • Aqueous cathode slurry processing is viable approach toward cheaper and greener LIBs. - Abstract: The positive electrodes based on nano- and micrometric carbon coated LiFePO4 (LFP) powders are prepared via aqueous slurry processing using “normal” and “intensive” mixing procedures. The XRD, XPS, and electrochemical characterization reveal that the “intensive” mixing process improves the discharge C-rate capability of the n-LFP cathode however provokes formation of an undesirable thin surface layer enriched by Fe3+ species. The waterborne graphite anodes and LiFePO4 cathodes for the energy and power cells are being developed, upscaled and manufactured on a pilot plant. Energy LiFePO4/C pouch cells demonstrate outstanding durability maintaining 80% of initial discharge capacity (IDC) after 7450 and 2400 full cycles under 1D and 4D discharge currents, respectively. Moreover, further cycling of the energy cell working under 1C/4D protocol reveals its extra-long secondary life (70% of IDC on 9200th cycle). Power LiFePO4/C pouch cell shows long lasting cycle life retaining 80% of IDC after 3350 cycles under harsh cycling conditions (3C/8D). The reported results are being achieved despite confirmed water release from lithium iron phosphate cathodes to the electrolyte. Finally, viability of aqueous processing of the electrodes without sacrificing electrochemical performance of LiFePO4/C batteries is clearly proven.
[en] Highlights: • Nanolaminate thin films of Al2O3/TiO2 with different bilayer density were prepared by ALD method. • A new multidimensional reconstruction method was implemented to analyze the nanomechanical response of the samples. • Mechanical response of the nanolaminates showed to be improved by layer thickness and follow the behavior of a nanocomposite coating. • The method implemented allows the reconstruction of 4D mechanical data at the nanoscale. A novel method of nanomechanical testing of multilayered Al2O3/TiO2 nanolaminates was implemented by the nanoindentation technique. The indentation data were reconstructed and filtered by a statistical analysis algorithm and presented as a function of the penetration depth of the indenter. Results show the increment of mechanical properties on the laminates as a function of the amorphous interfaces of the individual layers and the effective control of the wear rate of the structures for further applications. The results presented show both important insights on the mechanical behavior of nanolaminates and the further applicability of the reconstruction model for error reduction on mechanical testing of nanolaminate samples.