CATL has confirmed that its landmark aviation battery system for passenger electric vertical take-off and landing (eVTOL) aircraft has passed a “world-first” safety test, showing no thermal runaway propagation when two adjacent cells were deliberately triggered simultaneously. The 350 Wh/kg prismatic-cell system is now ready for mass production and will first power passenger aircraft from Autoflight, a Chinese eVTOL maker backed by CATL.

The test itself sets a materially higher bar than current industry practice. Manufacturers typically verify only that a single triggered cell will not cause a chain reaction across a battery pack; CATL triggered two adjacent cells simultaneously, at both a central and a corner location within the pack. Representatives from the Civil Aviation Administration of China were present to witness and verify the production, inspection and testing processes throughout, laying the groundwork for eventual civil aviation certification.

CATL’s relationship with Autoflight is nothing new, dating back to August 2024 when it first became a strategic investor with an outlay in the hundreds of millions of US dollars. The development marked its first publicly disclosed investment in an eVTOL company. The two firms went on to unveil a floating vertiport in November 2025: a battery-powered vessel combining an eVTOL landing platform with solar energy storage and charging systems. The vertiport was successfully demonstrated at Dianshan Lake using a two-tonne aircraft from Autoflight’s existing range.

Autoflight itself is one of China’s most established eVTOL developers, founded in 2017 and holding cumulative commercial orders for 2,000 aircraft going into 2026. Orders span multiple models, including the Prosperity and CarryAll. It has already made some deliveries, including a five-seat Prosperity to a customer in Japan in spring 2024, claiming the world’s first civil eVTOL delivery in the one-tonne weight class. The company has since logged demonstration flights across distances of up to 123 km.

Clearly, eVTOLs represent an attempt by CATL to diversify beyond its core automotive and energy storage businesses. However, the physics behind aviation batteries explain why the firm is very unlikely to extend this bet into long-haul commercial aviation. Jet fuel carries roughly 12,000 Wh/kg of energy against current electric vehicle (EV) batteries’ roughly 200-280 Wh/kg. Even CATL’s own aviation-grade cells max out at around up to 500 Wh/k.

Because an aircraft’s fuel burns off and lightens the plane during flight while a battery’s weight stays constant from take-off to landing, a fully electric transoceanic airliner would need to be built almost entirely of battery mass, leaving practically no room for passengers or cargo. Decarbonisation of the aviation segment remains heavily focussed on alternative fuels, perhaps most prominently hydrogen.

Instead, CATL is building toward shorter-range and higher-margin flight. Urban and regional routes of 20 to 150 miles are already achievable with 300 to 350 Wh/kg packs in small passenger aircraft. Aviation-grade cells, which demand far stricter safety tolerances and higher discharge rates than commoditised EV batteries, carry meaningfully better margins at a time when EV battery pricing faces intensifying competitive pressure. 

The same non-propagating cell design work required for aviation certification also has a plausible path back into CATL’s higher-performance automotive packs. CATL’s eVTOL push functions less as a bet on replacing jet aircraft and more like an attempt to strengthen and hedge against its own core business. Aviation certification doubles as safety research that feeds back into automotive batteries, while the segment itself offers margin insulation from an EV market CATL already dominates but which is prone to demand and price shocks.