At the European Electric Vehicle Batteries Summit, this week in Berlin, Imec presented a solid-state lithium-ion battery with an energy density of 400 Wh/l at a charging speed of 0.5 C (2 hours to fully recharge). Although a record, it’s not enough to surpass liquid-electrolyte Li-ion batteries, which currently max out at about 600 Wh/l. There’s room for improvement for both technologies, but more for the solid-state version, Imec believes. The research center’s roadmap aims for 1000 Wh/l at 2-3 C by 2024 (less than half an hour to recharge).
The Leuven-developed solid nanocomposite electrolyte has a high conductivity of up to 10 mS/cm, with potential for even higher conductivities. A distinguishing feature of the new material is that it’s applied as a liquid via wet chemical coating, and only afterward converted into a solid. That way, it’s perfectly suited to be cast into dense powder electrodes where it fills all cavities and makes maximum contact, just as a liquid electrolyte does.
Imec has started upscaling cells of the new solid-state battery technology on a pilot line at the Energyville Campus, a Flemish energy research alliance. The assembly process requires only minor modifications to existing Li-ion battery manufacturing lines.