Geely is developing a solid-state battery for electric vehicles that it says will reach an energy density of 500 watt-hours per kilogram, and the company has already begun validation testing under real-world conditions during 2026, ahead of a pilot deployment of the cells across several of its brands in 2027.
This density, if achieved at the cell level, would represent a major leap compared with technologies currently in use. High-nickel NMC cells in electric vehicles typically reach around 250–300 watt-hours per kilogram at the cell level, while Tesla’s 4680 cells approach 245 watt-hours/kg. LFP cells, which are widely used in lower-priced vehicles, have a lower density, and the figures fall further when modules, structural components and connections are included in the battery pack.
What Could Change in Electric Vehicles?
Doubling energy density enables two main paths: maintaining the same driving range while approximately halving the battery’s weight, or using the same weight to significantly increase range. Geely says vehicles using these cells could offer a range exceeding 1,000 kilometers on a single charge, a range it describes as close to that of diesel-powered vehicles. The company also announced that the service life could reach one million kilometers, or approximately 621,000 miles.
Reducing battery weight affects more than range; from an engineering perspective, it could also allow the vehicle’s overall mass to be reduced, lowering the energy required for movement. However, these benefits remain dependent on achieving the figures in a manufacturable product at an appropriate price, rather than in experimental or low-volume cells.
Geely’s Program and Materials Partner
The project is being developed within Geely Holding, which owns the Geely, Zeekr, Lynk & Co, Volvo, Polestar, Lotus and Smart brands. According to the company, real-world validation began in 2026, while the 2027 pilot deployment is intended to cover these brands, without specifying particular models or the expected production volume.
Geely named Dow Chemical as a materials partner, saying Dow developed an adhesive for solid-state cells that is expected to remain stable between 40 degrees Celsius below zero and 120 degrees Celsius, according to Bo Tong, Dow’s technical official. The ability to operate across a wide temperature range is considered one of the important challenges in solid-state battery development.
The announcement follows Geely’s commitment in January to build its first solid-state battery pack in-house and install it on an existing electric vehicle platform for testing. The target of 500 watt-hours/kg represents an advanced stage of that program.
What Has Not Yet Been Clarified?
A pilot deployment in 2027 does not mean that mass-produced vehicles will reach customers in the same year. A pilot production line tests the ability to manufacture cells repeatedly and in limited volumes, whereas commercial production requires cost reductions and assurances of reliability and safety at scale. Geely has not specified a date for mass production.
The company has also not disclosed the battery chemistry, including whether the electrolyte is sulfide- or oxide-based, or what type of anode is used. The company’s materials contained inconsistent indications as to whether the 500 watt-hours/kg density is calculated at the cell or pack level. Independent data on the charge and discharge cycles supporting the one-million-kilometer lifespan claim is also not yet available.
Competitive Context
CATL is also targeting pilot production in 2027 for a sulfide-based solid-state cell with a density of 500 watt-hours/kg, while BYD is looking toward all-solid-state battery offerings during the same period before commercial production later in the decade. Toyota has also indicated the launch of its solid-state battery between 2027 and 2028. Therefore, the similarity of the timelines alone does not determine any company’s ability to reach a reliable commercial product.