Sales of electric vehicles (EV) are rising as public acceptance continues to grow. Yet for US producers, they appear to be slow to act.

The US lags behind China and Europe in EV production and use, and the gap widens between 2017 and 2020, according to a study by the International Council on Clean Transportation (ICCT ).

US automakers produced more than 10 million electric passenger vehicles globally between 2010 and 2020, the report said. At the end of 2017, the US produced 20 percent of the global pool.

By the end of 2020, however, US producers accounted for only 18 percent of the cumulative number of EVs produced since 2010.

Meanwhile, China and Europe have seen their production shares rise.

China becomes the largest EV producer between 2010 and 2020, accounting for 44 percent of global EV production, with approximately 4.6 million units produced and sold over the ten-year period.

Europe accounts for 25 percent of global production between 2010 and 2020, with 2.6 million units built and 3.2 million units sold.

The global average share of EVs in new light vehicles in 2020 is 4.2 percent. Europe's share of this is 10 percent, China is over 6 percent, and the US is only 2.3 percent.

Tesla has held the top spot among US EV manufacturers, but a Bernstein report this week observed that consumer enthusiasm for Tesla is waning.

A survey of 457 Tesla owners showed that while owners remain avid supporters of Tesla, more customers will choose not to buy a Tesla in the future and instead buy a European luxury car brand.

In addition to reflecting the growing choice consumers have in EV, the report says, the data may also signal a cooling of excitement among first-time buyers.

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