By SETH BORENSTEINWASHINGTON (AP) â¿¿ 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 ultra-efficient 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 â¿¿ lithium ion. But a Jan. 7 battery fire aboard a Dreamliner in Boston, followed by a similar meltdown in Japan, led authorities around the world to ground the fleet this month, highlighting a longstanding safety problem that engineers have struggled with. In 2006 and 2007, more than 46 million cellphone batteries and 10 million laptop batteries â¿¿ all lithium ion â¿¿ 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 are costly, and they do not allow automobiles to go far enough between rechargings. A123, a maker of lithium ion batteries for electric cars, went bankrupt last year because of poor demand and high costs after receiving a $249 million federal grant. 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.