Tesla may have already begun testing its truck.
It's likely that Tesla has been testing a prototype truck on public roads for several months, according to the Morgan Stanley note.
According to a Reuters report, Tesla was in discussions with the Nevada Department of Transportation in June, addressing the possibility of testing two prototype trucks in the state.
It could have self-driving technology similar to Autopilot.
The semi-truck is expected to have self-driving technology that allows it to drive autonomously while traveling in platoons, according to a Reuters report that cited an email discussion between Tesla and Nevada Department of Motor Vehicles (DMV).
Tesla could introduce a battery swapping business or ultra-fast recharging to help with the truck's range.
To compete with traditional diesel trucks, Tesla may offer new charging solutions.
"Tesla will have to clearly address these issues at the event to be able to sell the idea of an
electric semi-truck to a deeply skeptical industry," Jonas and Shanker said in the note.
The analysts said that it is unlikely the company would include a 1,000 KwH+ battery, which would provide a range of 600 to 700 miles, because it would be too expensive.
"Instead, we believe that Tesla would choose to put in a smaller battery (around 250-300 kWh) and choose to solve the range problem either through optional battery swapping or very rapid
supercharging/flash charging," Jonas and Shanker said.
The semi-truck may have a range of 300 miles per charge.
With a full charge, the truck will have a range of about 200 to 300 miles with an average payload, according to a Reuters report, which cited an executive for the fleet operator that met with Tesla.
To help put that into perspective, conventional diesel-powered trucks can travel up to 1,000 miles on a full tank.
And deliveries for the semi-truck could begin in 2020.
The big rig truck could go on sale as soon as 2020, according to the Morgan Stanley analysts.
Tesla should reach full-scale production for the semi-truck sometime in 2019.
Musk also said that the company will likely reach full-scale production for the semi in 18 months to two years.
Tesla may announce some of its trucking partners at the event.
Given that Tesla has already said it has been working with trucking companies on the design, it's possible the automaker would share who some of these partners are.
Its partners could include large truck carriers as well as shippers, according to a recent note from Morgan Stanley analysts Ravi Shanker and Adam Jonas.
Some potential partners include the trucking companies Schneider National and XPO, as well as FedEx, according to Jonas.
Tesla has been working with truck makers on the design of the vehicle.
Tesla CEO Elon Musk said the company is working with major truck companies to design the company's first all-electric semi-truck.
"We are showing off a working prototype at the end of September, but we have shown it to people who buy heavy duty trucking, and they all love it. They just want to know how many can they buy and how soon," Musk said during Tesla's annual shareholder meeting, hosted at the Computer History Museum in Mountain View, California, in July.
"We are getting them closely involved in the design process," he said.
Tesla is including the companies in the design process because it helps ensure their needs are met, Musk said.