Cost-effective energy storage stable in the long term is to be created by packaging large-area, flexible lithium cells. From an economic viewpoint, roll-to-roll methods with thin-coated metal films combined with noncombustible solid electrolytes are suitable above all. ProSoLitBat concentrates on the packaging in the form of a photonic process chain because laser processes are deployed for selective dissipating, joining, contacting and separating. The sub-project concentrates on packaging, material selection and associated characterization. The latter includes cumulated leak rate determination and other non-destructive test methods, whereby methods in microsystem engineering can also be deployed to provide suitable components. The project started recently pertains to "functional surfaces for energy recovery, energy storage and resource efficiency", part of the high-tech "Photonics research in Germany" strategy. Photonics are considered here as a tool for processing pliable materials, which is a subject of research itself given its special requirements (pliable, very thin and electro-chemically active layers).