As 21st century technology strains to become ever faster, cleaner and cheaper, an invention from more than 200 years ago keeps holding it back. It's why electric cars aren't clogging the roads and why Boeing's new ultraefficient 787 Dreamliners aren't flying high.
And chances are you have this little invention next to you right now and probably have cursed it recently: the infernal battery.
Boeing is the first company to make extensive use in an airliner of technology's most advanced battery - lithium ion. But recent problems with its battery highlight a longstanding safety problem that engineers have struggled with.
In 2006 and 2007, more than 46 million cellphone batteries and 10 million laptop batteries - all lithium ion - were recalled because of the risk of overheating, short-circuiting and exploding. Additional safety features have been installed since then on lithium ion batteries used in consumer electronics.
As for the electric car industry, lithium ion batteries have proved to have two major drawbacks: They're costly, and they don't allow cars to go far enough between rechargings.
Lithium ion batteries, which store more energy at a higher voltage and a lighter weight than earlier types, represent the most recent big jump in battery technology. And that took place nearly a quarter of a century ago.
"We need to leapfrog the engineering of making of batteries," said Lawrence Berkeley National Lab battery scientist Vince Battaglia. "We've got to find the next big thing."
But none of the 10 experts who talked to The Associated Press said they know what that big thing will be yet, or when it will come.
"If you crack it ... it'll change the world," said Carnegie Mellon University materials science professor Jay Whitacre.
Batteries are so crucial to a greener energy future that the Obama administration has spent more than $2 billion to jump-start the advanced-battery industry, including setting up what some experts say is a mini-Manhattan Project for batteries.
To make the next breakthrough, researchers will have to master complex chemistry, expensive manufacturing, detailed engineering, a variety of materials, lengthy testing, stringent safety standards and giant cost problems. It will involve dealing with liquids and solids, metals and organic chemicals, and things in between.
Experts say lithium ion batteries are more dangerous because their electrolyte, the liquid that allows ions to move between electrodes in the battery, is more flammable than the substance in older type batteries, which include the lead-acid batteries in most cars and the nickel cadmium batteries often used in video equipment and power tools.
Still, MIT materials science and engineering professor Gerbrand Ceder and others said the safety problems can be fixed.
One of the nation's best hopes for a breakthrough, said Battaglia, is John Goodenough, the man responsible for the 1979 breakthrough that led to the first commercial lithium ion battery in 1991.
Goodenough is 90.
"I'm working on it," Goodenough, an engineering professor at the University of Texas-Austin, said Tuesday. "I'm optimistic in a sense that I'm willing to keep working on it. I think we can do some interesting things."