In a possible first step toward a new source of energy, researchers in China have developed a battery system that can capture and generate electricity from atmospheric nitrogen.
Nitrogen is the most abundant gas in Earth’s atmosphere, and could provide an almost limitless source of energy if it could be harnessed, which a research team at the Changchun Institute of Applied Chemistry, part of the Chinese Academy of Sciences, seems to have done, at least on an experimental scale.
The team led by Dr. Zhang Xin-Bo was investigating ways to improve the chemical process that makes existing lithium-nitrogen batteries work. In this type of battery, lithium nitride is broken down into lithium and nitrogen gas, with the energy of the reaction providing electricity.
The challenge, Zhang explained in an email, is that nitrogen has a strong chemical bond holding a pair of nitrogen atoms together, and does not break apart under normal conditions.
What they found to be easier to accomplish, he said, was to reverse the chemical reaction in a normal battery. In the team’s prototype, nitrogen gas in ambient conditions reacts with lithium to form lithium nitride, with the energy from that reaction creating electricity.
Zhang described the test battery as a “proof of concept,” as it was only able to produce electricity for a very short time. Its output, however, was similar to that of existing lithium-metal batteries.
“This promising research on a nitrogen fixation battery system not only provides fundamental and technological progress in the energy storage system but also creates an advanced N2/Li3N (nitrogen gas/lithium nitride) cycle for a reversible nitrogen fixation process,” said Zhang. “The work is still at the initial stage. More intensive efforts should be devoted to developing the battery systems.”