Tesla Inc. (NASDAQ:TSLA) employees are reportedly expecting further delays to the new Model 3 due to problems with battery production at the company’s Gigafactory in Sparks, Nevada.
Several employees and former workers told CNBC that Tesla has needed to make some of the batteries by hand and borrow staff from one of its suppliers to help with manual assembly.
READ: Tesla shifts sharply into reverse after cutting production guidance for Model 3
The staff also said many of the company's quality control workers were relatively inexperienced, make sloppy calculations and don't know how to identify flaws.
Tesla had already delayed production of the Model 3, its first mass-market electric vehicle, due to issues at the Gigafactory it launched last year.
In November, chief executive Elon Musk said in an earnings call that Tesla was working to fix the manufacturing issues that came to light a month earlier.
Mass production of batteries no closer
More than 400,000 people have already reserved the Model 3 by putting down a US$1,000 refundable fee.
Responding to the report, a Tesla spokesperson told CNBC: "Until we reach full production, by definition some elements of the production process will be more manual."
“This is something Elon and [CTO] JB [Straubel] discussed extensively on our Q3 earnings call, and it has no impact on the quality or safety of the batteries we're producing."
However, sources told CNBC that Tesla is still no closer to mass producing batteries for the basic US$35,000 model of the sedan.
Manual production could be dangerous, Tesla engineers warn
Two Tesla engineers also said making the batteries by hand could lead to a hazard.
Batteries that are shipped without the minimum gap required between lithium-ion cells could cause them to short out or catch fire, they said.
A Tesla spokesperson dismissed the claims as “false”, saying: "The implication that Tesla would ever deliver a car with a hazardous battery is absolutely inaccurate, contrary to all evidence, and detached from reality.”
The spokesman added: “Every battery in a Tesla vehicle has thousands of cells, the vast majority of which are at the same voltage potential as neighbouring cells. Hypothetically, even if two cells of the same voltage potential were touching, there would be absolutely zero impact, safety or otherwise – it would be as if two neutral pieces of metal touched.”
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Shares in Tesla rose 1.1% to US$341.60 in US pre-market, reversing a decline in the previous session.