Batteries are a promising technology for sustainable aviation. They have several advantages, including reducing in-flight emissions and decreasing dependence on fossil fuels. In the case of battery applications in aviation, safety and specific energy values are two of the most significant challenges [1]. It is therefore crucial to consider these parameters alongside other quantitative and qualitative metrics. Among the quantitative metrics, the number of cycles is particularly important. Among the qualitative metrics, recyclability is another fundamental dimension. There are different types of batteries of interest within this technology. Each presents its own benefits, limitations, and maturity level. A classification of battery technologies for use in aviation has been developed by the Environmentally Friendly Aviation for All Classes of Aircraft (EFACA) project. The project has also conducted in-depth analyses of the benefits and challenges of each technology, as well as their potential for future aviation applications. Further research is currently needed on certain critical battery parameters to enable their scaled use in aircraft propulsion applications. Future battery development is expected to enable short-range passenger flights [2]. It is therefore essential to clearly identify the main challenges associated with each type of battery, as well as the intermediate steps required to enable scalability. To understand the potential of using this technology for aircraft propulsion, it is important to define a roadmap for the main battery types. The presentation will cover the main battery types, their advantages and limitations, and a number of key considerations to be taken into account in developing a roadmap for using batteries as the propulsion source for sustainable aircraft in the future up to 2050. [1] V. Viswanathan et al., ‘The challenges and opportunities of battery-powered flight’, Nature, vol. 601, no. 7894, pp. 519–525, Jan. 2022, doi: 10.1038/s41586-021-04139-1. [2] M. Lindberg and J. Leijon, ‘Electrifying aviation: Innovations and challenges in airport electrification for sustainable flight’, Advances in Applied Energy, vol. 18, p. 100222, June 2025, doi: 10.1016/j.adapen.2025.100222.