Tesla could 'easily' start producing its Semi truck now, but it doesn't yet have enough battery cells to power them, Elon Musk said

• Tesla could "easily" launch production of its Semi electric truck right now, CEO Elon Musk said Wednesday.
• But it makes no sense to start production because Tesla doesn't have enough battery cells for the vehicles, Musk said.
• Musk added it's "highly likely" that the Tesla Semi would become the first vehicle to achieve full autonomy.

It "would not make sense" for Tesla to start making its Semi electric truck right now, even though it could "easily" launch production, the company's CEO Elon Musk said Wednesday.

The electric car maker doesn't have enough battery cells for the Tesla Semi, Musk said in a fourth-quarter earnings call.

Tesla now expects to begin delivering its electric semi-truck later in 2021, after originally saying production would begin in 2019.

It first unveiled the freight-hauling semi-truck four years ago.

"The main reason we have not accelerated new products is - like, for example, Tesla Semi - is that we simply don't have enough cells built," Musk said.

"If we were to make the Semi right now, and we could easily go into production with the Semi, but we would not have enough cells built for it right now," he said.

"Prototypes are easy, scaling production is very hard," he added.

The Tesla Semi would typically use five times as many cells as a car, Musk said, but wouldn't sell for five times the price.

Read more: How Tesla bounced back from worst mistake Elon Musk ever made and became the world's most valuable car company

At Tesla's "Battery Day" in September, the company said it planned to start making a "4680" battery pack, which it said would produce six times the power of a regular pack while being faster and cheaper to produce.

These will be used in the Semis, but the batteries won't reach large-scale production until 2022.

On Wednesday, Andrew Baglino, Tesla's SVP of powertrain and energy engineering, said the company would have the engineering knowledge, production processes, and equipment to reach its 100 gigawatt-hour goal by 2022.

"It would not make sense for us to do the Semi right now, but it will absolutely make sense for us to do it as soon as we can address the cell production constraint," Musk said.

In response to a question from Gene Munster, managing partner of Loup Ventures, Musk said it was also "highly likely" that the Semi would become the first vehicle to achieve full autonomy. Munster had pointed out that trucks such as the semi typically travel predictable highway routes.

Currently Tesla offers customers its "full self-driving" system as a $10,000 add-on, but this does not give the cars complete autonomy, as the driver must keep their hands on the wheel at all times.

Musk also said he thought Tesla will "definitely" make an electric van "at some point." He added that deliveries of Tesla's Cybertruck may start this year "if we get lucky."

During the earnings call, Musk announced that fourth-quarter revenues were up 46% year-on-year, to $10.744 billion, allowing the company to record an annual profit for the first time.

Tesla also unveiled both a refreshed Model S and the new Model X Plaid, a high-performance SUV costing $119,990.

Tesla stock has risen more than 650% in the past year, helping mint Musk as the world's richest person.