American researchers think they have found a way to make lithium ion batteries last longer — and the change requires extra cobalt.

The advancement is good news for battery metals suppliers because lithium ion batteries are made up of several commodities besides lithium, including graphite, cobalt and nickel.

It is also good news for players in the clean energy space because grid-scale energy storage requires batteries that can store a large amount of energy and roll it out over longer periods.

The discovery was made by scientists at the University of Maryland, the U.S. Department of Energy’s Brookhaven National Laboratory, and the U.S. Army Research Lab.

The scientists believe they can triple the energy density of lithium-ion battery electrodes.

An electrode is a conductor through which electricity enters or leaves an object.

The bottleneck

According to the University of Maryland, increasing the energy density of lithium-ion batteries could facilitate the development of advanced technologies with long-lasting batteries, as well as the widespread use of wind and solar energy.

“Lithium-ion batteries consist of an anode and a cathode,” said Xiulin Fan, a UMD researcher and one of the lead authors of the paper.

“Compared to the large capacity of the commercial graphite anodes used in lithium-ion batteries, the capacity of lithium-ion battery cathodes is far more limited.

“Cathode materials are always the bottleneck for further improving the energy density of lithium-ion batteries.”

Just add cobalt

Engineers at the University of Maryland synthesized a new cathode material – a modified and engineered form of iron trifluoride (FeF3).

FeF3 is more cost-effective and can provide higher capacities than traditional cathode materials.

To overcome the challenges of poor energy efficiency, a slow reaction rate, and poor cycling life resulting from the use of FeF3 previously, the researchers added cobalt and oxygen atoms.

“When lithium ions are inserted into FeF3, the material is converted to iron and lithium fluoride,” said Sooyeon Hwang, a co-author of the paper and a scientist at the Brookhaven National Laboratory.

“However, the reaction is not fully reversible. After substituting with cobalt and oxygen, the main framework of the cathode material is better maintained, and the reaction becomes more reversible.”

American car giant Tesla and Japanese battery maker Panasonic have previously vowed to cut their use of cobalt in their batteries, but industry players needn’t worry — the sheer scale of battery storage manufacturing is going to soar, according to Bloomberg New Energy Finance’s (BNEF) latest report.

“We see $548 billion being invested in battery capacity by 2050, two thirds of that at the grid level and one third installed behind-the-meter by households and businesses,” said Seb Henbest, head of Europe, Middle East and Africa for BNEF.