That's because the higher your cholesterol, the greater your chance of developing heart disease. Nanotubes made of carbon might help make batteries that are lightweight, cheap and powerful. Battery weight, price and capacity are some of the biggest hurdles in the manufacture of affordable electric cars. Carbon nanotubes are strong, flexible carbon tubes one-50,000th as wide as a human hair. A team of physicists from the National University of Singapore has shown that carbon nanotubes can be used to store hydrogen gas, an energy carrier that can be used in rechargeable batteries and fuel cells.
Carbon is lighter and cheaper than many of the materials used in today's batteries.
Carbon normally doesn't absorb hydrogen gas except at extremely low temperatures and high pressures. But by adding metals such as lithium or potassium to the carbon nanotubes, the scientists showed that the nanotubes absorbed hydrogen at relatively modest temperatures. Furthermore, the nanotubes absorb more hydrogen for their weight than other hydrogen-storing materials. The research appeared in a recent issue of the journal Science.