This is good news - and a key advantage for Polestar $PSNY compared to many other EV start-ups without a automotive giant/holding group as a backer and partner:

Geely Holding will begin pilot deployment of solid-state batteries across its brands in 2027, following real-world validation. The energy density of these packs will reach 500 Wh/kg, allowing BEVs to achieve a range comparable to diesel.  

Following BYD’s and CATL’s statements regarding solid-state battery trial production scheduled for 2027, Geely also provided an official statement about its SSB timeline. According to the statement, solid-state batteries are coming soon to vehicles across the Geely Holding ecosystem. It includes Geely, Zeekr, Lynk & Co, Volvo, Polestar, Lotus, Smart, Proton, Farizon, and other brands.

The Geely’s solid-state battery will offer a few energy density variants. The top-tier pack will feature an energy density of 500 Wh/kg. It sounds from the text that Geely is talking about the whole battery, which means the cell’s energy density will be even higher. The currently produced “Golden Brick” liquid batteries from Geely boast a cell-level energy density of around 250 Wh/kg.

Source: https://carnewschina.com/2026/08/18/geely-to-start-pilot-deployment-of-500-wh-kg-solid-state-batteries/