The most important goals of industrial robotics have always been to maximize production and simplify man’s work; for these reasons, more and more companies have started developing robotic systems based on the concept of modular robotics. The flexible approach allows engineers to reduce loads, costs, and development time and, at the same time, satisfy a larger range of clients. This thesis deals with modularity in the vehicle electrification field, through the development analysis of a cartesian robot for battery laser welding. The project was carried out in collaboration with a Comau team, by designing a compact industrial product to be configured according to the client requests and delivered through standard transportation.