South Korean electric vehicle (EV) battery manufacturer SK On Company announced that it has completed the construction of a pilot plant for test production of all-solid-state batteries (ASSBs) in Daejeon, a city located around 140 km south of Seoul.

The new pilot plant will produce sulphide-based solid-state battery prototypes for customers to evaluate and verify in terms of quality and performance. The facility will also look to develop and produce lithium-metal ASSBs, which use lithium-metal anodes instead of graphite anodes for improved energy-density, as well as weight and volume reduction.

SK On confirmed that the new 4,600-square-metre test facility will use a “warm isostatic press-free technology” production process, which applies uniform pressure to electrodes at elevated temperatures to improve energy density and performance, for the first time in the country.

SK On president, Lee Seok-hee, said in a statement: “This pilot plant will serve as a cornerstone for SK to leap forward as a strong and resilient company in addressing any changes in the business environment.”

SK On aims to launch commercial production of ASSBs at a separate facility in 2029, a year ahead of its previously announced schedule. The company aims to commercialise ASSBs initially with an energy-density of 800 watt-hours per liter (Wh/L), rising to 1,000 Wh/L later on.

Last year, SK On partnered with Solid Power Inc, an all-solid-state battery (ASSB) technology developer based in the US state of Colorado, to accelerate the development and commercialisation of ASSBs.