Rail is mainly a decarbonized mean of transport, but a portion of the railway network remain unelectrified and currently operated with diesel train. Trains with onboard batteries are a solution to maintain the same operation on these sections while avoiding GHG emissions but are complex systems that raises several questions regarding operation & infrastructure. While a separated solution could be investigated by each actor (operator, infrastructure manager), the goal is to minimize the life cycle cost of a railway system. In this article the French existing regional trains rolling stock fleet, the existing infrastructure or the new partial electrification evolution, and the operation modes are considered to evaluate the issues and opportunities brought by battery trains.