Still, little-known to the outside world despite its huge success, Sunra is China's leading maker of electric vehicles (EVs) with an annual production capacity of more than four million EVs of various makes. It's also been the world's top-selling EV brand for the past five years.

Now, this company has set its sights on India, which it sees as the world's biggest market for electric bikes (e-bikes) within the next decade. It plans to set up a factory in India to not only build the popular e-bikes (or bikes with small electric motors) but its other EVs such as Electric Scooters; Electric Motorcycles; Electric Tricycles and Electric Cars. Sunra exports its e-bikes and spares to some 70 countries.

Based in Wuxi in Jiangsu Province and with production plants in five other Chinese provinces, Sunra says it's upbeat about investing in India. It's delighted about Indian Prime Minister Narendra Modi's encouraging policies for the EV sector and his invitation that companies like Sunra manufacture their EVs in India.

Sunra is studying India's policies and wants to build a factory in India, most likely in Bangalore (Bengaluru), said Sunra General Manager Victor Lu. Lu is confident India will outpace China in four or five years in terms of demand for e-vehicles.

He said his company sees India as the world's biggest market for e-bikes "and we want to tap into it." He said the high levels of pollution in Delhi and other Indian cities means people will want to switch to e-bikes very soon. In addition, the Modi government's decision to encourage the use of e-vehicles "is all the more reason for us to invest in India."

India is the world's second-largest greenhouse gas emitter after China and has many of the world's most polluted cities. India's extensive pollution is one of the reasons the Modi government wants India to switch to e-vehicles. New Delhi estimates switching to e-vehicles will also significantly slash India's oil bill and reduce motor vehicle emissions by 37 percent.

According to the World Health Organization (WHO), the top 10 most polluted cities in the world based on the pervasiveness of microscopic PM2.5 (particulate matter with a size of 2.5 microns) in the atmosphere are (from most polluted to least polluted): Kanpur, Faridabad, Varanasi, Gaya, Patna, Delhi, Lucknow, Agra and Muzaffarpur.

All these cities are in India. The only non-Indian city on the list is Bamenda in Cameroon, which is number eight.

Lu said Sunra already has a presence in India with its exports of batteries, spares parts and e-bikes. Sunra's Indian operations are small-time, said Lu, and so are its partners. "Now, we want to go big," he said.

On the bright side, Sunra already has two Sunra bike models on Indian roads. Lu said a further six models are currently being tested by the "Automotive Research Association of India."

Lu said Sunra currently makes only 20 percent of its bikes for the Indian market, "but we want it to be 80 percent in the future."

In 2017, 777,000 EVs were sold in China compared to 507,000 in 2016. This makes China the leader in both the supply and demand for EVs.