Chinese electronics company Xiaomi has revealed a new patent that outlines a solid-state battery design, marking its formal entry into the development of next-generation battery technology. The move aligns Xiaomi with a growing list of global players working to overcome the technical barriers limiting commercial adoption of solid-state batteries.
The patent, recently published, describes a layered electrode structure designed to enhance both ionic conductivity and energy density. At the core of the system is a current collector embedded with multiple electrode material layers made from active substances, conductive agents, binders, and a solid polymer-based electrolyte containing metal salts. The structure enables the electrolyte to penetrate deeply through the electrode, shortening ion transport paths and potentially improving battery performance.
Xiaomi indicated the design is compatible with current lithium battery production infrastructure, which could ease future mass production efforts. The company claims its prototype battery supports a Cell-to-Body (CTB) structure with a 77.8% volume efficiency. With a pack height of 120 mm, including the vehicle floor, the design reportedly enables better space utilization and vehicle stability. Xiaomi estimates a CLTC range of more than 1,200 kilometers and a fast-charging capability of up to 800 kilometers in 10 minutes.
Xiaomi’s entry comes amid broader efforts by automakers and battery firms to commercialize solid-state technologies. BMW has initiated road testing of a solid-state prototype, while companies like CATL, BYD, and SAIC are targeting low-scale production around 2027. Toyota is also working toward a commercial launch by 2028.
Solid-state batteries are considered a key innovation for electric vehicles, replacing the flammable liquid electrolyte used in conventional lithium-ion cells with solid materials. Though these batteries promise improvements in energy density, thermal stability, and safety, challenges persist, particularly in ion mobility, interfacial resistance, and material stability. Three main types of solid electrolytes—sulfide, oxide, and polymer—are under development, each with its own benefits and drawbacks.
Xiaomi’s patent suggests it is addressing one of the major bottlenecks in the field—ion transport through thick electrodes—raising the prospect of integrating solid-state battery packs in its own electric vehicle lineup. Analysts note this could reduce its reliance on third-party suppliers like CATL and BYD in future models, including a potential successor to its SU7 EV.
