The growing demand of batteries for electric mobility enhances the overall environmental impact of battery production. Among the different cathode cell chemistries, the Ni-rich layered oxide LiNi x Co y Mn z O2 (NCM)-based cathode active material (CAM) is regarded to have the lowest global warming potential of around 75.5 kg CO2-Eq/kWh1, whereas ≈25 % is attributed to cell manufacturing. The global warming potential could be reduced by 16 % via aqueous cathode electrode production2, as water instead of N-methyl-2-pyrrolidone (NMP) as processing solvent is generally advantageous in several aspects e.g., not necessitating solvent recovery. However, Ni-rich NCMs are water sensitive and prone to structural degradation, leading to e.g., particle cracking and surface layer reconstructions. Consequently, lithium and transition metals dissolve in the aqueous media forming soluble (such as LiOH and Li2CO3) and insoluble (such as NiOOH) species.3 The formation of LiOH leads to an increase in pH and can cause corrosion of the aluminium current collector.Promising strategies for aqueous processing are either based on CAM coating, processing aspects (e.g., functionalized binders, electrode paste additives) or electrolyte additives. A common processing additive is phosphoric acid, which is aimed to lower the pH, protect the aluminium current collector, and form a protective Li3PO4 layer on the NCM particle surface. However, further investigations are required to gain a full understanding of the NCM interphase changes and to evaluate other interphase engineering strategies to overcome the remaining obstacles.In this study, the well-known strategies are evaluated with respect to electrochemical performance of LiNi83Co12Mn05O2||Graphite cells. Each strategy is applied within a characteristic time scale of NCM path, i.e., from synthesis to end-of-life (see scheme 1), and reveal characteristic advantages and disadvantages on cathode particle degradation and interphase formation.References M. Mohr, J. F. Peters, M. Baumann and M. Weil, Journal of Industrial Ecology, 24(6), 1310–1322 (2020).K. Shen, Q. Zhai, Y. Gu, W. Wang, H. Cao, M. Hauschild and C. Yuan, Resources, Conservation and Recycling, 198, 107152 (2023).M. Hofmann, M. Kapuschinski, U. Guntow and G. A. Giffin, J. Electrochem. Soc., 167(14), 140535 (2020). Figure 1
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