During the first 18 months of the project, a complete set of eco-design criteria were established to guide the consortium towards the selection of the most interesting materials that will compose the battery in term of sustainability, limitation of critical raw materials, safety, recycling, and potential cost from the manufacturing process of the materials. In addition, several case scenarios were defined by the industrial partners to analyze different technico-economic targets to guide the consortium partners toward the most realistic and challenging cell device. The materials and cell design is also guide by the latest EU regulation and recycling process from individual materials to the cell level.
In term of technical activities, a dedicated work was performed to develop a new generation of solid-state hybrid electrolyte comprising an organic and inorganic phases. Both phases ar developed at lab-scale prior being upscaled in order to obtain a sustainable biopolymer acting as organic phase compatible with the selected halide inorganic phase. During the first months of the project, the nature of the polymer and inorganic were varied to define a good combination of materials prior being attempting in the form of an hybrid mixture. The electrolyte acting as battery separator, another strong part was devoted to the design of a dedicated Li metal electrode. In this regards the thickness and microstructure of the Li was investigated as well as its elaboration process to minimize the interfacial contact resistance, ensure homogeneous Li deposits, and use an interlayer to make compatible the hybrid electrolyte. For the cathode side, the main task was to synthesize in different ways families of cathode materials without critical materials to be later on implemented in a complete electrode comprising the hybrid-electrolyte. Moreover, a benchmark of cathode current collector was done to design a protective layer deposited on top of the current collector to ensure low contact and high corrosion resistances.
As complementary activity to the design and characterization of the battery materials, safety analysis was initiated to help to refine the selection of the most suitable material along with the development of an in situ electrochemical cell adapted to imaging technique. Similarly, recycling of each project materials was done to assess on the complete recycling path to reach the goal set by EU in term of recycled material proportion within a battery cell.
Overall, the work performed during the first 18 months of the project open the door to a new generation of solid-state lithium battery device with many technical achievements that needs to be consolidated to move toward a practical and reliable battery cell.
