[en] While energy storage is at the heart of current challenges related to energy transition, and more particularly battery-based energy storage, the authors first shows that this battery-based storage is a major vector of energy transition. They mention the different solutions associated with a flexibility of production and consumption. They propose an overview of the different storage technologies associated with the different types of energy (electrochemical, chemical, electric, thermal, kinetic of potential mechanical). Then, they discuss the various characteristics and technologies of battery-based storage. They outline the usefulness of this storage for the different actors (producer, network manager, market operator, industrial, user). They discuss economic, technical, organisational, administrative blocking points to be overcome for a massive deployment of battery-based storage in France. However, they notice that the context is rather favourable in France, and propose an overview of recent initiatives in France (political will, regulatory evolution, experimentations, investments, innovating start-ups, panel of actors). In the next part, they discuss challenges and perspectives for the French sector on the national and international markets, and propose a road-map to make leaders emerge