Especially as staff training is a continuous process, focused on real needs. The training process is highly complex and time-consuming, and must include the technical skills needed to manufacture battery cells properly (i.e. safe handling of chemicals and operating machinery) and understand the correlations between parameters . The use of immersive technologies such as VR for professional training has become widespread in other disciplines, with demonstrated improved efficiency and quality of procedural tasks in several fields such as healthcare and automotive industry - . Due to total immersion, and therefore the impossibility of perceiving the outside environment, the main disadvantage of VR is that it has to be used in rooms with a large amount of space, and is therefore impossible to use in real workspaces (like a battery manufacturing pilot line or a battery factory), which might be cluttered and which are subject to strict safety regulations . MR, which lets the Ergonomics is described as a "scientific discipline concerned with the understanding of interactions among humans and other elements of a system, and the profession that applies theory, principles, data, and design methods to optimize human well-being and overall system performance ". Ergonomics helps make humanmachine interaction more intuitive by keeping the human in the center . Ergonomics provides a batch of efficient methods to analyze the real activity of the users and highlight the needs and constraints they face during their activities. Subsequently, ergonomics allowed us to include future users in the design process of our MR infrastructure, in order to understand user scenarios, their tasks and their working environment and then build an optimal and comfortable user experience that corresponds to their real needs .