CATL's aviation battery clears safety test — but Western skies are a different story
CATL, the company that already supplies roughly a third of the world's EV batteries, has passed a key aviation safety test for a new battery designed for electric air taxis. The 350 Wh/kg prismatic cell cleared a dual-cell thermal runaway test witnessed by China's civil aviation authority, the CAAC — a first for a battery at this energy density. The result matters because it establishes a real certification pathway in China, not just a lab demonstration.
The test
Standard industry practice triggers a single cell and watches whether fire spreads to its neighbors. CATL's test went further, triggering two adjacent cells simultaneously at both the center and corners of the pack — conditions that better reflect worst-case in-flight scenarios. The pack did not propagate thermal runaway beyond the triggered cells, according to Automotive World. CATL says the battery is ready for mass production.
The catch for Western markets
Passing a CAAC-supervised test is not the same as earning FAA or EASA certification. Those are separate regulatory systems, and neither has finalized battery-specific standards for eVTOL aircraft. The FAA is still in early research on electric aircraft fire-fighting guidance, with no confirmed energy density requirement for Part 23 eVTOL certification, per a 2026 GAO report. Any eVTOL maker wanting to fly passengers in the US or UK would need to go through that process independently — CAAC approval doesn't transfer.
CATL's confirmed first customer is Autoflight, a Chinese eVTOL developer in which CATL invested hundreds of millions of dollars starting in 2024. Autoflight has separately been exploring US and UK certification routes, but those remain works in progress. An earlier claim that CATL is developing eVTOL aircraft jointly with state-owned planemaker COMAC has no confirmation from English-language sources; the verified partner here is Autoflight.
Why the energy number matters
Current electric car batteries typically land between 250 and 300 Wh/kg. Getting to 350 Wh/kg in a prismatic cell — a format easier to stack and cool than cylindrical cells — meaningfully reduces the weight penalty that has kept electric flight impractical beyond short hops. It doesn't solve range for long routes, but it's the kind of improvement that makes urban air taxi economics start to look plausible.
CATL has previously announced a "condensed battery" targeting 500 Wh/kg, but the certified pack here uses the 350 Wh/kg prismatic cell. No evidence links the condensed technology to this specific CAAC-approved system.
For now, China has the first certified aviation battery at this density. Whether that certification translates into aircraft flying over London or Chicago depends on regulators who are still writing the rules.
