The transition from a fossil-fuel powered economy towards decentralized renewable energy sources and electric mobility creates a global demand for battery cells. As cell manufacturers ramp up production capacity, they are facing the challenge of scaling their IT systems in pace with the growing demand. Innovations such as new cell types and enhanced production technology as well as incorporating ever-evolving data-driven methods, e.g., Artificial intelligence, require a versatile IT architecture, capable of adapting. In the light of these challenges, this paper introduces a methodology aimed at building an IT architecture tailored to the requirements of a given battery cell manufacturing use case. It provides different approaches with respect to several dimensions, considering among others the requirements of shopfloor connectivity, data acquisition and storage strategies, as well as IT systems integration design. Further covered requirements deal with computational capacities close to the shopfloor, real-time aspects, data ingestion and integration, and dynamic resource allocation. This paper presents the application of the methodology to a multi-site high-scale production at Fraunhofer FFB, describing the resulting IT architecture. The factories combined will host four manufacturing lines producing a GWh-scale battery cell output per year. To sustain the workload on the FFB IT architecture incurred by this throughput, the design of the IT architecture pivots away from a strictly hierarchical structure, bringing critical systems and databases closer to the shopfloor. This and other design choices have been made based on the developed methodology. Overall, the presented methodology and the derived FFB IT architecture show a path towards building a battery cell production IT architecture capable of scaling and rapidly adapting to new technologies.