China’s Contemporary Amperex Technology Co. Ltd., known as CATL, unveiled its strongest battery to date Wednesday, saying that it could one day be used to power electric aircraft.  

The battery, which loads more power into a smaller package, has an energy density of 500 watt-hours per kilogram, CATL’s Chief Scientist Wu Kai said during a presentation at the Shanghai auto show. CATL’s most recent battery, called Qilin, has an energy density of 255 Wh/kg and can power an electric vehicle for 1,000 kilometers (620 miles) on one charge. 

The technology, which CATL calls a condensed state battery, is potentially a breakthrough that will help electrify sectors wed to fossil fuels because existing batteries are either too heavy or unsafe. Still, questions remain about the materials it will use, its cost and ultimate market impact.

CATL, the world’s biggest maker of EV batteries, plans to start mass production of the new cell, which will mainly be used initially for cars, this year, and critically at a lower energy density than the 500 Wh/kg it claims it can reach for aircraft. CATL is collaborating on developing a civilian electric aircraft using the technology, Wu said. The company declined to say whom it was working with, citing confidentiality agreements. 

Research from BloombergNEF shows a clear trend to increase energy density in battery packs — which also brings lower cost, better safety and durability — according to data compiled in May last year, but no battery companies or startups have set as high a target as CATL, BNEF analyst Jiayan Shi said.

Shi said CATL’s newest battery was a type of solid-state battery technology, and could be “very significant” as CATL advances its R&D. Solid-state cells overall, however, while considered next-generation are still several years away from maturity and mass-production.

While CATL didn’t specify what the condensed state battery will cost for electric cars, it said it will be 10 times that figure for aircraft.

Moody’s Investor Service vice-president Chenyi Lu said it was “too early to call” CATL’s new battery technology “a game changer,” pointing to a certification process the cell will first need to prove its capabilities.

In his speech, Wu said the condensed state batteries create a micron-level net structure that increases the efficiency of lithium-ion transportation without compromising safety. They have innovative anode materials and separators and can use a variety of high-energy cathode materials, he said, without specifying what they were.

A CATL spokesperson said the compressed state battery technology is different to experimental solid state or semi-solid state batteries, which CATL sees as still having unresolved scientific and technical problems.