Tesla will announce a major new product line in April, Elon Musk has just teased.

The founder and CEO of Tesla is his own press relations company, because whenever he tweets, it makes headlines. Musk recently used Twitter to hype up an event that would unveil an over-the-air software update for the Model S sedan, for instance, but now he is using Twitter to get the world excited about an entirely new announcement.

"Major new Tesla product line -- not a car -- will be unveiled at our Hawthorne Design Studio on Thurs 8pm, April 30," Musk has tweeted, meaning Tesla plans to unveil something other than a car in exactly one month. Musk hasn't offered any other clues, though Tesla confirmed in March that it planned to launch in the coming months a stationary battery pack for homes.

Tesla specifically said it was working on a consumer battery pack for the home - and that the design of the battery was already complete but production wouldn't begin for another six months. It was assumed at the time that the home battery pack would be like the Toyota Mirai, which uses a hydrogen fuel cell and can power the average home for a week when fully charged.

That said, in December, Musk claimed Tesla was working on a robotic charging system that automatically plugs into its electric cars and apparently moves and looks like a "solid metal snake". Musk didn't specify if it would be limited to Supercharging stations or your house, nor did he provide a release date, but the charger will work with all existing and future Model S cars.

READ: Tesla is making a car charger that moves and looks like a 'solid metal snake'

Most reports have suggested Tesla's event on 30 April will have something to do with the stationary battery back for homes, rather than the snake charger, but nobody actually knows for sure until the electric car manufacturer makes things official.