CATL, which produces more than a third of the EV batteries sold worldwide, filed a 527-page document to the Hong Kong Stock Exchange with offer-related information redacted.

It is the first step in what analysts say could be a jumbo initial public offering that could boost Hong Kong's fortunes as a listing hub.

The firm submitted an application proof in "draft form", which includes financial information and corporate details with redactions.

CATL said in another exchange filing dated Tuesday that it had appointed overall coordinators and listed seven financial institutions.

The company is publicly traded in Shenzhen and its plans to seek a secondary listing in Hong Kong were announced in an exchange filing in December.

Founded in 2011 in the eastern coastal Chinese city of Ningde, CATL has grown into the world's largest EV battery maker and supplies firms including Mercedes-Benz, BMW, Volkswagen, Toyota, Honda and Hyundai.

CATL said in the exchange filing that it had "established six major (research and development) centers and 13 battery manufacturing bases worldwide, with service outlets spanning 64 countries and regions" as of September.

"By the end of November 2024, our EV batteries were installed in approximately 17 million vehicles, which represents one in every three EVs worldwide," it said.

The funds raised will be used "to advance the construction of Phase I and II of our Hungary project", as well as for "working capital and other general corporate purposes", according to the document.

CATL is building its second European factory in Hungary after launching its first in Germany in January 2023.

- Robust support -

In January, the US Department of Defense added CATL to a list of companies it says are affiliated with Beijing's military.

China has denounced the move as "suppression", while CATL denied engaging "in any military related activities".

CATL's Shenzhen shares are down nearly three percent since the start of the year.

The company has benefited from robust financial support from Beijing, which has prioritised the development of domestic high-tech industries that it views as strategically advantageous.

At home, the firm's success in recent years has been galvanised by rapid growth in the domestic market.

Hong Kong's stock exchange is eager for the return of big-name Chinese listings in the hope of regaining its crown as the world's top IPO venue.

The Chinese finance hub saw a steady decline in new offerings after a regulatory crackdown by Beijing starting in 2020 led some Chinese mega-companies to put their listing plans on hold.