It can happen to anyone, and often it does. It starts with the ominous bleep, then the flashing battery icon. You try to warn the other caller, but in mid-sentence, your cell phone shuts down, leaving the screen blank and you standing on the street corner dumbfounded, murmuring a futile “Hello?”

If Murphy had a law for modern-day communication, it might go something like this: A cell phone’s battery will only die when you need it the most. It’s a scenario that two entrepreneurs, Tom Kim, 25, and John Lin, 28, of JK One, Inc., hope to cash in on with their new battery-charging service.

With the new service, cell-phone owners can recharge their batteries in less than 20 minutes for $2 a charge when they stop by a participating newsstand or deli in more than 70 locations throughout the city.

“We think it will be great convenience for cell-phone users that depend on their phones for business,” Mr. Kim, a founding member of JK One, Inc., said.

The express charger, made by Korea-based manufacturer Awon, accommodates all cell-phone models, even older versions, and charging times can range anywhere from 10 to 20 minutes, depending on the battery’s age and capacity.

The device has already become widely popular in countries like Korea and Japan, where it first hit the streets in 2001. “The cell-phone technology is a lot more advanced than it is here,” Mr. Kim said. “People use their cell phones like credit cards to purchase items. And all of them have video cameras. With all these extra functions, they use up their batteries faster. So they have these charging devices everywhere.”

With cell-phone technology in America slowly catching up, Mr. Kim predicts the express chargers may one day become as commonplace as ATM machines. He and his partner have bought about 200 charging machines at $250 apiece from the Korean manufacturer, after seeing a commercial for them on Korean television. They hope their investment will introduce the device to cell phone users in New York City.

The service, which was first introduced last October, is still in a trial phase. “In Korea, cell phones are in constant use, so it has become a necessity. But I think people here are a bit more hesitant to try it,” Mr. Kim said. To help drum up business, JK One loans each charger to participating vendors in exchange for half of the proceeds. The idea is to increase the product’s visibility, while also expanding their profits.

Vendors say the device has been slow to catch on. Mohammed Alam, a newsstand owner on 30th Street and Broadway, said his charging device has only attracted about 65 customers in the last six months.

“Most phones take about twenty minutes to charge,” Mr. Alam said. “And most people don’t want to wait around, especially in the winter.”

Mr. Alam plans to keep the charger through the summer, hoping that business will pick up during the warmer months. “It is getting better,” he said. “In the last 10 days, we had 12 customers.”

Liz Willis, a newsstand vendor on 50th Street, was more hopeful. “I have been getting a lot of inquiries,” she said. “And I think as the weather gets better, people will be willing to wait. It will be good for business because people probably buy a bottle of water or candy as their phones charge.”

Mr. Kim said the service can attract anywhere from 250 to 500 customers a week throughout its 70 locations. Chargers offered near nightclubs often generate the most usage, as do some of the major business districts, where workers are often dependent on cell phones for business transactions. Tourist areas also generate a lot of business, Mr. Kim said.

But tracking usage patterns is not an exact science. “The place where we thought the chargers would do really well, like Penn Station, they have not,” Mr. Kim said. “Meanwhile, we put one on Seventh Street and Second Avenue, and they get a good amount of usage. It is hard to figure out.”

JK One soon plans to take the device beyond the streets. “We have already received a lot of calls from businesses who want the device for their offices,” Mr. Kim said. “We are also looking into hotels. It is going to take some time. But it is pretty exciting to watch it grow.”