Updated to include details on new Apple investment.

Share repurchases and dividend payouts are not helping revive Apple's  (AAPL - Get Report) lagging stock price. So is it time for the tech giant to tap its sizable cash pile and buy a game-changing business to excite investors?

One possibility bandied about -- electric car maker Tesla (TSLA - Get Report) , which is a place that often serves as a talent pool for Apple.

Apple "could certainly [buy Tesla] if they wanted to. They certainly have the financial capacity to do so," said former Apple CEO John Sculley in an interview with TheStreet. "If they chose to [buy a big company] I am sure they would only do it with a product that was intended to be revolutionary in a large addressable market. So an automobile maker like Tesla would certainly meet that criteria."

However, Sculley noted the company "has no history of buying a really big company, so they would have to think about that a lot as to how they would incorporate it and manage it." The last sizable business of any kind that Apple bought was headphone and music subscription purveyor Beats for $2.6 billion back in 2014.

Since then, Apple has continued down a path of acquiring small upstarts with promising future technology, while watching its cash hoard balloon. The company now has over $250 billion in total cash, which represents about half of its market cap.

Apple purchasing Tesla to gain access to the company's advanced battery technology and electric car capabilities is not such a far-fetched idea. "In our view, acquiring Tesla's advanced battery technology would greatly accelerate Apple's entrance into the next-generation auto arena, and we estimate valuable economies of scope could be realized while transitioning to mass-market volumes (e.g., consumer electronic batteries, automotive software, etc.)," wrote FBR & Co. analyst Dan Ives in a note earlier in the year.

Musk fueled the rumors last year, too, when he confirmed a meeting with Apple's head of M&A. He didn't specify who exactly he met.

Then again, Apple may not need to do any big acquisitions to regain the confidence of Wall Street.  Said Sculley, "Just refreshing the installed user base of the iPhone is going to be huge. The iPhone 6 was successful and I suspect they have an iPhone 7 coming that will be just as successful."

Added Jim Cramer and Jack Mohr of Action Alerts PLUS in a recent note, "We remain confident in Apple, and will continue to hold this name for the long term -- Apple isn't simply a hardware company, it is an ecosystem that engenders long-term loyalty and constantly innovates on behalf of its customers."

Apple is a holding in Jim Cramer's Action Alerts PLUS Charitable Trust Portfolio. Want to be alerted before Cramer buys or sells AAPL? Learn more now.

In the end, don't expect Apple to telegraph any acquisition large or small. "Apple has always been stealth," concluded Sculley. The former Apple exec wasn't kidding about Apple being stealth with its investments. Didi, a Chinese ride-hailing startup and competitor to Uber, said Friday that Apple will invest $1 billion in its business. The company said the iPhone maker will help it build up its ride-sharing platform in China.