Florence Lambert joined the CEA (The French Alternative and Atomic Energy Commission) in February 2000 and assumed various managerial functions related to renewable energy storage systems.

In 2006, she was one of the founders of the French National Institute for Solar Energy (CEA-INES) and initiated the first research platform for stationary storage in Europe.
From 2009, she developed the transportation division of CEA-LITEN, focusing on the development and integration of two major components: lithium-ion batteries and fuel cells, and played a key role in various low-carbon vehicle developments in France.

Since 2013, as Director of the CEA-LITEN Institute which gathers 1000 researchers, she leads a team covering different technological fields: solar PV, decarbonized transport, hydrogen, carbon cycle and material recycling. This innovation institute focused on Energy Transition technologies is the 3rd largest in the world (after NREL/US and Fraunhofer-ISE/Germany) and the 1st in terms of inventiveness (over 210 patents/year). This institute is at the heart of many industrial projects (SAFT, ACC, Symbioin particular) or ambitious demonstrators (Energy Observer).

At the same time, on the institutional level, and since 2013, she has overseen the national industrial plans for energy storage, under the responsibility of the Ministry of Economy ("La nouvelle France Industrielle") which gave rise to the current ambitious projects and the French H2 roadmap presented in 2018.

In June 2018, Florence Lambert was appointed President of the Industry, Jobs and Innovation Commission at the SER Board of Directors.

In February 2019, Florence Lambert was appointed President of the World Solar PV Conference, EUPVSEC 2019, following the nomination and voting process of the International Scientific Advisory Committee, the first woman to achieve this distinction in 35 years.

In March 2021, she was named "Woman of the Year 2020" in the Innovation category by the Green Universe media.

Finally, on the same date, she took over the presidency of GENVIA, which is a Clean Hydrogen Technology Venture created to accelerate affordable clean hydrogen production, energy storage and fuel applications at scale.