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Cost-effective production of low cobalt Li-ion battery (LIB) cathode materials is of great importance to the electric vehicle (EV) industry to achieve the zero-carbon economy. Among the various low cobalt...

Slug flow has received increased interest due to the slugs serving as individual microreactors for enhanced process efficiency and product quality. In this study, slugs were continuously generated in various scales and sizes, with slug size uniformity studied by in‐line imaging. Different strategies of gas flow control and slug scale‐up were evaluated regarding the slug size distribution. With modified gas flow control, the slug uniformity was improved significantly. Slug flow can also be scaled up without sacrificing slug size uniformity, either by increasing the reservoir feeding volume or the flow rate. The type of gas used (air and nitrogen) to generate slugs does not affect the slug size uniformity. A narrow slug size distribution can improve the particle size distribution and, hence, lead to better product quality.

Lithium nickel manganese cobalt oxide (NMC111) is considered to be one of the most promising cathode materials for commercial lithium-ion battery (LIB) fabrication. Among the various synthesis procedures of NMC111, hydroxide co-precipitation followed by lithiation is the most cost-effective and scalable method. Physical and chemical properties of the co-precipitation product such as yield, particle size, morphology, and tap density, depend upon the various reaction parameters, which include pH, chelating agents, metal salt concentrations, and stirring speed. As a consequence, detailed theoretical and experimental modeling is critically required to not only understand the interdependence between the particle properties and reaction conditions but also optimize these parameters. In this study, theoretical modeling was performed to analyze the role of various NH 4 OH concentrations with varying pH on the yield of the NMC(OH) 2 product. From the experimental findings, it was observed that the product obtained at a pH of 11.5 and NH 4 OH concentration of 0.02 M possessed the highest tap density. Three of the hydroxide precursors with different tap density values were chosen to lithiate and were applied for coin cell fabrication. The NMC(OH) 2 precursor with the highest tap density had the highest specific capacity of 155 mAh g −1 at 0.1 C and retained up to 78.6 mAh g −1 at 5 C. The variation of the Li + diffusion coefficient for the three selected materials was also studied using electrochemical impedance analysis.

Li[Ni0.8Co0.1Mn0.1]O2 (LNCMO811) is the most studied cathode material for next-generation lithium-ion batteries with high energy density. However, available synthesis methods are time-consuming and complex, restricting their mass production. A scalable manufacturing process for producing NCM811 hydroxide precursors is vital for commercialization of the material. In this work, a three-phase slug flow reactor, which has been demonstrated for its ease of scale-up, better synthetic control, and excellent uniform mixing, was developed to control the initial stage of the coprecipitation of NCM811 hydroxide. Furthermore, an equilibrium model was established to predict the yield and composition of the final product. The homogeneous slurry from the slug flow system was obtained and then transferred into a ripening vessel for the necessary ripening process. Finally, the lithium–nickel–cobalt–manganese oxide was obtained through the calcination of the slug flow-derived precursor with lithium hydroxide, having a tap density of 1.3 g cm–3 with a well-layered structure. As-synthesized LNCMO811 shows a high specific capacity of 169.5 mAh g–1 at a current rate of 0.1C and a long cycling stability of 1000 cycling with good capacity retention. This demonstration provides a pathway toward scaling up the cathode synthesis process for large-scale battery applications.