Prototype battery powers itself with nitrogen in the air

Nitrogen gas is literally everywhere, and a new battery design puts it to use.

Nitrogen is the most abundant gas in Earth’s atmosphere, which has made it a tantalizing option for generating renewable energy. However, the strong bonds holding nitrogen gas together mean it’s not easily broken apart to transfer the chemical energy of its bond into electricity. In a new study published in Chem, researchers have developed a "proof-of-concept" battery that is the reverse of existing lithium-nitrogen batteries. Instead of generating energy from the breakdown of lithium nitride into lithium and nitrogen gas as standard batteries do, it uses nitrogen gas in the atmosphere to react with lithium and form lithium nitride. The prototype battery’s energy output is short-lived, but comparable to that of other lithium-metal batteries.

This is an artistic illustration of Zhang and colleagues' proof-of-concept experiment, which successfully implements a reversible nitrogen cycle based on rechargeable Li-N2 batteries with promising electrochemical faradic efficiency. Credit: Zhang et. al.

“The conversion of atmospheric nitrogen gas (N2) into valuable substances is critical to industry, agriculture, and many other processes that sustain human life,” said study author Xin-Bo Zhang, who is a professor at Changchun Institute of Applied Chemistry. “Nowadays, despite some significant achievements, artificial nitrogen conversion still faces challenges, such as complex and expensive catalysts and electrolytes, irreversible reactions, and low yields under mild conditions.”

Yet Zhang and his colleagues have made progress in overcoming these obstacles, achieving a reversible artificial nitrogen reaction and energy conversion under room temperature and at atmospheric pressure, conditions that are of course necessary for a battery to be useful in everyday applications.

However, before the battery can be used widely, a number of issues will need to be resolved. “The Li-N2 battery still faces many challenges: the stability of the Li anode, the need to improve the cathode and electrolyte, the need for more effective nitrogen conversion catalysts. And the battery reaction mechanism needs more work,” says Zhang. “If these issues are resolved, the Li-N2 battery will one day be available to the public.”

Featured image courtesy of Zhang et. al.