As part of the work on deliverable D6.7, PEPPERONI partners have inspected encapsulants, precursors, and interconnection materials to ensure that all materials meet the required quality standards for efficient and reliable photovoltaic (PV) module manufacturing. For encapsulants, properties like thermal stability, chemical composition, and viscosity are analysed, and advanced methods are used to address specific challenges of tandem cells. Precursors are tested for purity and stability. Suitable interconnection materials are checked for thermal and mechanical properties. The results provide a clear framework for material characterisation and optimisation. The methods will continue to be applied throughout the project, ensuring high quality production and improving the scalability of tandem solar cell technologies. Future work will focus on further refinement and application of these protocols.