Li Auto Explains Why ONE Uses a Three-Cylinder Range Extender, Confirms Shift to In-House 1.5T Four-Cylinder Starting with L9

On February 27, Tang ("@LaoTangGe"), Head of Product Line at Li Auto, explained why the Li ONE originally adopted a 1.2L three-cylinder range extender: when the company was founded in 2017, it lacked in-house engine development capabilities, suitable 1.5L four-cylinder range extenders were unavailable on the market, and the range-extended electric vehicle (EREV) approach itself was not widely favored at the time. Ultimately, Li Auto chose Dongan’s 1.2L three-cylinder engine because its power output and physical dimensions best matched the vehicle’s requirements. To address the NVH (Noise, Vibration, and Harshness) issues commonly associated with three-cylinder engines, Li Auto reinforced the engine block, optimized the camshaft design, and implemented custom acoustic packaging. These measures enabled the Li ONE to rank among the top ten vehicles in an independent third-party NVH ranking in 2019. Currently, the new Li L9 is equipped with Li Auto’s self-developed third-generation 1.5L four-cylinder range extender. Tang explicitly stated that the company will no longer use three-cylinder range extenders in the future, as superior alternatives are now available.