NEW HAVEN >> The molecule that carries oxygen through our bloodstream could help create much longer-lasting batteries, according to research at Yale University. The blood molecule, called a heme, also could reduce the amount of blood that is wasted when animals such as cows and pigs are slaughtered, according to a press release from Yale. The new fuel cells are known as lithium-oxygen batteries, which have a much longer life than the standard lithium-ion batteries used in cellphones, electric cars and other devices. The challenge with lithium-oxygen batteries is that they produce lithium peroxide, which then covers the oxygen electrodes, reducing their efficiency. Scientists needed to find a catalyst to turn lithium oxide back into lithium ions and oxygen gas, according to the release. The blood molecule that facilitates this process is called a heme, one of the molecules in hemoglobin, which carries oxygen in the blood. \u201cHeme is the base molecule for hemoglobin,\u201d said Andre Taylor, professor of chemical and environmental engineering at Yale. \u201cWe use the heme molecule for the batteries because it has a strong oxygen affinity.\u201d When oxygen binds to the heme molecule, the lithium peroxide is broken down, allowing the electrode to function more efficiently. Lithium-oxygen batteries can go weeks without recharging, much longer than lithium-ion batteries. An extra benefit of using the heme molecule is that its use in manufacturing batteries would reduce the amount of wasted blood in food production. \u201cWe\u2019re using a biomolecule that traditionally is just wasted,\u201d said Taylor in the release. \u201cIn the animal products industry, they have to figure out some way to dispose of the blood. Here, we can take the heme molecules from these waste products and use it for renewable energy storage.\u201d The research was published Wednesday in Nature Communications. The lead author is Won-Hee Ryu, a former postdoctoral researcher in Taylor\u2019s lab, who is now a professor at Sookmyung Women\u2019s University in South Korea.