Tesla CEO Elon Musk has pushed back the unveiling of an "unexpected product" by two days, saying it needed "a few more days of refinement."
On October 9, Musk tweeted that Telsa would reveal a product on Oct. 17 that was "unexpected by most."
Recode reported that it was possible Musk planned to unveil a new version of the company's at-home energy storage devices, called the Powerwall and the Powerpack, as he'd promised to do by the end of 2017.
Another possibility was that the entrepreneur would launch Autopilot 2.0, an updated version of the company's semi-autonomous driving system, Recode said.
Also on Sunday, Telsa and Panasonic announced that they had teamed up to collaborate on the manufacture of photovoltaic (PV) cells and modules in Buffalo, New York.
Under the terms of the deal, which will only go ahead if shareholders approve Tesla's takeover of SolarCity, Telsa will undertake to make long-term purchases of PV cells and modules from Panasonic, which it will use in a solar energy system that works with the Powerwall and Powerpack.
Panasonic will start production in Buffalo to meet Tesla's requirements from 2017, according to a joint statement from the companies.
Tesla offered to buy SolarCity in late June, but the deal has been criticized by skeptics for a variety of reasons, such as being a poor use of Tesla's cash or a distraction for Tesla executives.
Musk has insisted, however, that SolarCity's business would complement Tesla's stationary storage products, such as the Powerwall and Powerpack, helping the company to provide a fully integrated, sustainable energy system.