The 2013 Tesla Model S has received rave reviews, including the best score that Consumer Reports has given any car in six years.

The stock of Tesla Motors [NSDQ:TSLA] is on a roll, the company is delivering hundreds of its Model S all-electric luxury sport sedan every week, and it just turned in its first-ever profitable quarter.

What can Tesla do for an encore?

Betting seems to be that CEO Elon Musk will shortly announce that the company will offer battery-pack swapping for the Model S at locations across the country.

Tesla plans $200 million in capital expenditure this year, according to its recent annual report, and it has referred to building "specialized public facilities to perform [battery] swapping" that it might construct as well as Tesla Stores and service centers.

Musk still has two out of five announcements left in the series he announced some weeks ago.

Company followers expect one to cover expansion of the Supercharger quick-charging network.

That network allows drivers traveling between city pairs perhaps 300 miles apart to stop for a half-hour recharge that refills the battery pack to 80 percent of its energy capacity.

But the battery swapping--which Tesla has discussed several times over the years--seems likely to be the other announcement, as detailed on Green Car Reports.

"There is a way for the Tesla Model S to be recharged throughout the country," Musk recently tweeted, "faster than you could fill a gas tank."

Battery swapping is really the only method that would allow a completely recharged car to be provided in less than 10 minutes.

Stay tuned for the latest in the string of surprises from what has to be, this year, the country's most surprising automaker.