Periodic Reporting for period 2 - PSIONIC (High voltage, room temperature single-ion polymer electrolyte for safer all solid state lithium metal batteries)
Okres sprawozdawczy: 2024-01-01 do 2025-06-30
Solid-state polymer electrolytes and lithium metal anodes address these challenges by replacing flammable and unstable liquid electrolytes and enabling dendrite-free cycling of high-energy lithium metal cells manufactured through sustainable and cost-effective processes. The PSIONIC project advances the development of all-solid-state battery technology by employing amorphous cross-linked polyethylene oxide (PEO) laminated on thin lithium foil at the anode and a high-voltage cathode coated with a single-ion conductive polymer.
During the first 18months, the PSIONIC project has been able to design a new positive electrode formulation; the latter is based on NCM 811 cathode active material, and uses a single ion polymer as the catholyte. As the aim of the project being to reduce the ecological footprint of batteries compared to current existing technologies, this cathode needed to be manufactured by a dry process, ie. Using any organic solvent, which has been achieved. Performing electrodes have been extruded by the partners and their performances have been assessed successfully.
In parallel, cheap solid polymer electrolytes have been developed and characterized ; they perform well at room temperature, opening the way for cheaper lithium metal battery designs that do not need any heating to deliver power. Currently, these electrolytes are being transferred to full systems to validate their compatibility with the positive electrode just described above.
Last but not least, the lithium metal anode is under improvement; partners work with thin lithium metal foils currently, around 30µm thick but they are improving it to reach even thinner films in order to reduce cost and improve energy density.
In parallel to the chemistry development activities, PSIONIC consortium is also focused on the recycling of the different element composing the future cell ; to that purpose, partners work not only on the lithium metal recovery but also the different polymers and the active material. Proof of concepts have been already made to recover active material in model lithium metal polymer chemistries.
Building on RP1, RP2 has seen substantial progress across materials, processes, and sustainability goals:
o Single-ion conductive polymers were synthesized at kilogram scale, demonstrating promising ionic conductivity and compatibility with high-voltage cathodes.
o Electrolyte formulations have advanced significantly, with several candidates approaching 4.5 V anodic stability, a key milestone for high-voltage operation.
o Nanometric polymer coatings were successfully applied to NCM particles, enhancing interface stability and contributing to improved cell performance.
o 30 µm lithium reels were successfully prepared.
o Dry processing of electrodes was confirmed, aligning with the project's ecological footprint reduction goals.
o Room-temperature operation of solid polymer electrolytes was validated.
o Lithium recycling efficiency exceeded 60%, with promising results for full cell component recovery.
While some targets such as cycle life, cost reduction, and large-scale production are still under development.