  Open access to research data is increasingly important for accelerating
research. Grant authorities therefore request detailed plans for how data is
managed in the projects they finance. We have recently developed such a plan
for the EU-H2020 BIG-MAP project - a cross-disciplinary project targeting
disruptive battery-material discoveries. Essential for reaching the goal is
extensive sharing of research data across scales, disciplines and stakeholders,
not limited to BIG-MAP and the European BATTERY 2030+ initiative but within the
entire battery community. The key challenges faced in developing the data
management plan for such a large and complex project were to generate an
overview of the enormous amount of data that will be produced, to build an
understanding of the data flow within the project and to agree on a roadmap for
making all data FAIR. This paper describes the process we followed and how we
structured the plan.
