CATL Advances Solid-State Battery Development with 20 Ah Cells Ahead of 2027 Trials

CATL has scaled up its all-solid-state battery development, moving from a 10 Ah-class validation platform to 20 Ah sample trials, according to Y-Auto. The company is targeting small-batch production by 2027, with large-scale manufacturing slated for around 2030. The update was shared by CATL on October 27 via the Shenzhen Stock Exchange’s Hudongyi platform in response to investor questions. The development team currently exceeds 1,000 people, and the programme aims for an energy density of approximately 500 Wh/kg. However, CATL has not officially confirmed that figure as a final production-cell specification, nor has it disclosed expected trial output, specific automotive customers, or a vehicle launch date tied to the cells. Beyond energy density, the company faces hurdles regarding durability, manufacturing yield, cost, safety, and real-world performance. Chairman Robin Zeng previously rated CATL’s solid-state tech at Level 4 on a nine-level readiness scale. Sulfide-based cells present specific technical challenges, including interface stability as electrodes expand and contract during charge and discharge cycles, managing contact pressure and interface resistance, and protecting materials from moisture to prevent the release of toxic hydrogen sulfide gas. While the 500 Wh/kg goal suggests high-capacity anode architectures such as lithium-metal or anode-less designs (similar to approaches described by Samsung SDI), CATL has not specified the exact anode configuration used in these latest cells. Other industry players are pursuing similar timelines: Toyota and Idemitsu aim to commercialise sulfide-based all-solid-state batteries for BEVs between 2027 and 2028, while Samsung SDI targets mass production in the second half of 2027, eyeing humanoid robots as a potential early application alongside EVs. Unlike semi-solid or hybrid designs that retain liquid electrolytes, all-solid-state cells rely entirely on solid electrolytes, making repeatability and cost-competitive manufacturing the central hurdles for CATL.