(Bloomberg) -- Global electric-vehicle battery sales more than doubled in the first four months of the year as the switch to environmentally-friendly cars gathers pace.

Sales of EV batteries rose to 65.9 gigawatt-hours in the January-April period, from 26.8 gigawatt-hours a year earlier, SNE Research said Tuesday.

Contemporary Amperex Technology Co.’s sales almost quadrupled to 21.4 GWh, cementing the Chinese company’s position as the world’s biggest EV battery maker with 32.5% of the global market.

“Despite the hit of Covid-19 pandemic in 2020, the company’s performance has rapidly resumed,” CATL said in a statement. The firm is focused on building “long-term cooperation with international automakers,” it said. CATL won about 16% of revenue from overseas sales last year up from 4% in 2019, according to BloombergNEF.

Demand for electric vehicles is increasing as countries work to reduce carbon emissions, consumers embrace cleaner automobiles and costs tumble. Automakers such as Volkswagen AG and Ford Motor Co. are plowing billions of dollars into adding more EV models to their lineups, while industry pioneer Telsa Inc. posted estimate-smashing deliveries in the first quarter.

“CATL, BYD and other Chinese makers led the market growth,” SNE said in the statement. “With the Chinese market expected to continue expanding, growth for most of the Chinese makers is expected to exceed the market average.”

EV sales in China may climb more than 50% this year alone, research firm Canalys estimates.

South Korean companies also posted strong growth, helped by rising EV demand in Europe. Sales at LG Energy Solution Co. and SK Innovation Co. more than doubled in the first four months, while Samsung SDI Co. posted 88% growth.

(Updates with CATL comment in fourth paragraph)

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