ChristopherWolverton's super-lithium battery could theoretically work just fine. In a daunting task, the battery USES oxygen to drive chemical reactions, which researchers previously thought would cause the battery to become unstable, but experiments have found that not only does the battery work properly, but it performs extremely well.
Working with researchers at Argonne national laboratory, the Wolverton research group at Northwestern university has developed a rechargeable lithium-iron-oxide battery, which has more lithium ion cycles than conventional lithium-cobalt-oxide batteries. Can be made into higher-capacity batteries and can keep smart phones and electric cars on the go.
"Our predictive calculations for this battery response are very promising, but without the confirmation of the experimental process, there will be a lot of skepticism," said Wolverton, a professor of materials science and engineering at Northwestern university's McCormick school of engineering.
Lithium-ion batteries work by shuttling lithium ions back and forth between the anode and the cathode. As the battery charges, the ions move back to the anode, where they are stored. The cathode is made of a compound of lithium ions, transition metals and oxygen. When lithium ions move from the anode to the cathode and return, cobalt can effectively store and release electrical energy, and the cathode capacity is then limited by the number of electrons in the transition metal involved in the reaction.
"In the traditional case, the transition metals can be reaction," Wolverton said, "because every cobalt represent only a lithium ion, so has the limitation of storage battery, what's worse, the current mobile phones or laptops in lithium batteries are usually only use half of the cathode."
Lithium cobalt - oxide battery has been listed for 20 years, but researchers for cheaper, substitute for higher capacity. Wolverton's team used two strategies to improve the normal lithium cobalt - oxide battery: use iron instead of cobalt, oxygen and forced to participate in the reaction process.
If oxygen can also store and release electricity, the battery will be more efficient storage and the ability to use lithium. While the other team has tried the strategy in the past, but few people realize this. "Before the problem often lies in the fact that if you try to make the oxygen reaction, compounds will become unstable," Yao said, "oxygen will be released from the battery, the reaction is irreversible."
Through calculation, Wolverton and Yao found a reversible formula. First, they use for cobalt iron, which is the most advantage, because it is one of the cheapest elements in the periodic table. Secondly, through calculation, they found that the lithium ions, iron ions and oxygen ion the right balance, to make oxygen and iron ion drive reversible reaction, at the same time without oxygen evolution.
Wolverton said: "not only the battery will be a very interesting chemical reactions, because we from metal and oxygen, rather than to obtain electronic iron. This is likely to make better batteries will also be cheaper." More importantly, fully rechargeable battery driven by four lithium ion, the reaction can be reversible to use one of these lithium ion, significantly more than the capacity of the battery. But, to drive the reaction with iron and oxygen, can make all four circulation extremely promising.
Wolverton said: "each metal containing four lithium ion - this will change everything lithium battery." This means that your phone can last eight times of life, or your car can continue to drive eight times, if the electric car in the scope and cost to compete with gasoline-powered cars even more than it, it will change the world energy market.