Chinese electric car startup Nio has entered another four European countries, including Germany, but executives say they have a long way to go before they can catch up with local rivals although they are optimistic about the future.

The New York-listed carmaker held an event in Berlin on Saturday, announcing that its service is now available in Germany, Denmark, the Netherlands and Sweden. It entered Norway in 2021 as its first stop in Europe.

Different from the Norwegian market where it sells vehicles, Nio offers a subscription mode in the four countries, citing unattractive tax policies in these markets.

The subscription mode allows customers to rent Nio's three models — two sedans and one SUV — for as short as a month.

In addition to getting the vehicles charged, customers can swap their dead batteries for fully charged ones at Nio's swapping stations.

A station has just opened in Zusmarshausen, on a motorway between Munich and Stuttgart. The plan is to install at least 120 battery swapping stations in Europe by the end of next year, said William Li, founder and CEO of Nio.

The company opened its first European plant to manufacture swapping stations in Hungary last month.

Despite media reports that Nio is launching an offensive to take on behemoths like BMW, Li told journalists on Saturday the carmaker is still like a "pupil" compared with those car giants.

"Europe is the home turf of our respectable rivals, and they have a much deeper understanding of local customers and the car market. So they are definitely the examples we want to learn from," he said.

But Li said that Nio has its advantages as well, including its innovative solutions.

He added that China's competitive edge in the smart electric car industry ranging from supply chains to professionals will prepare Chinese companies to take the lead in the long run.

Li and Qin Lihong, Nio's co-founder and president, drove an EL7 SUV through 10 European cities including Frankfurt and Oslo for 10 days before the Berlin event.

Qin said compared with big cities in China, he saw fewer electric vehicles on the streets of those cities.

"That means we are here before the real advent of the EV boom, so for us Europe is full of opportunities," said Qin, who oversees Nio's business in Europe.

Nio also plans to introduce its volume brand, whose project name is Alps, into Europe as well after it will be unveiled in 2024.

The relationship between Nio and Alps is like that of Audi to Volkswagen or Lexus to Toyota.

"You can tell from the name that we will bring it into Europe," said Li.

He said there was a proposal to call the project Qomolangma but he dismissed the idea because it may sound a little arrogant for a startup project.

But Nio does eye its global opportunities. The carmaker aims to be present in 25 countries and regions by 2025.

"We would like to aspire to have a 25 percent share of the world's premium car market," said Li. "But let's not talk about the deadline. It would be too stressful."