Imec announced a solid-state Li-metal battery cell with an energy density of 400 Wh/L at a charging speed of 0.5C (2 hours). Imec also announced it has started to upscale the materials and processes in a pilot line for fabrication of solid-state pouch cells at the EnergyVille Campus in Genk (Belgium) and is collaborating with the University of Hasselt. imec anticipates surpassing wet Li-ion battery performance and reaching 1000 Wh/L at 2-3C by 2024.

Imec says its researchers are working to replace the wet electrolyte with a solid material, which provides a platform to further increase the energy density of the cell beyond that of cells based on liquid electrolyte. The solid nanocomposite electrolyte that the company says its R&D center has developed has a high conductivity of up to 10 mS/cm, with a potential for even higher conductivities. A distinguishing feature of the new material is that it is applied as a liquid—via wet chemical coating—and only afterward converted into a solid, when it is already in place in the electrodes. This method is suited for casting the material into dense powder electrodes, where it fills all cavities and makes maximum contact, just as a liquid electrolyte does.

Using that solid nanocomposite electrolyte along with a standard lithium iron phosphate (LFP) cathode and lithium metal anode, imec has fabricated this improved battery with an energy density of 400 Wh/L at a charging speed of 0.5C (2 hours).

The company also has begun upscaling the cells for this new solid-state battery technology, including a 300 m2 battery assembly pilot line, which includes a dry room of 100 m2. This conventional A4 sheet-to-sheet wet coating-based line is suited for processing of the solid electrolyte. As such, the assembly of the new cells could be done by slight modification of existing manufacturing lines for Li-ion batteries. This means the new technology would not need expensive investments to switch from wet to solid-state cells. The new pilot line, which is located at the EnergyVille Campus and is set up with the University of Hasselt, allows manufacturing of prototype pouch cells of up to 5 Ah capacity.

“The new battery demonstrates that our breakthrough electrolyte can be integrated in performant batteries. The pilot-line allows us to take the next step and upscale the battery breakthrough to industrially relevant processes and formats, using manufacturing processes similar to those for wet batteries,” said Philippe Vereecken, Scientific Director at imec/EnergyVille.