Cobalt plays a vital role in today’s lithium batteries as a relatively rare and valuable heavy metal. But scientists at the University of Texas at Austin have come up with a new type of electrode that has no cobalt at all but has the same performance as conventional lithium batteries. In addition to saving manufacturing costs, it is also important for people involved in mining and environmental protection.
Powder samples will be made into cobalt-free electrodes (from UT Austin)
Cobalt is known to have excellent conduction and durability throughout the charge and discharge cycle. It has been a key material for lithium electrodes since its inception.
However, the negative impact of the mining industry on the environment and workers’ health (exposure to dangerous doses of toxic metals and natural landscapes/degradation of water) has come under increasing criticism in recent years.
With this in mind, many research teams are looking at alternative electrode materials that are lower cost or more environmentally friendly. These include an experimental battery developed by IBM that features materials extracted from seawater.
But the team at the University of Texas at Austin is developing another new electrode structure that is completely cobalt-free.
Typically, manufacturers use a mixture of metal ions, including cobalt, nickel, and aluminum, to make electrodes. None of the most expensive is cobalt, which can even account for about half of the total cost.
Study author Arumugam Manthiram said: “Cobalt is the least abundant but most expensive ingredient in battery electrodes. The good news is that we are completely removing our dependence on it”.
By adjusting the formulation to replace with a new electrode material containing 89% nickel and replacing the rest with manganese and aluminum, the research team has been able to achieve this goal.
The key is to have ions of different metals evenly distributed across the cathode during the synthesis process to overcome the main drawbacks of other designs — because ions accumulate in specific locations, thereby reducing battery performance.
The new battery structure has other advantages, such as a higher nickel content that stores more energy, meaning further growth in electric vehicle mileage, or mobile device life.
“We also increase the energy density and reduce costs of our batteries without sacrificing cycle life,” says Arumugam Manthiram.
Finally, to bring the technology to market, the research team set up a start-up. Details of the study have been published in the recently published journal Advanced Materials.
Originally titled “High-Nickel NMA: A Cobalt-Free To NMC and NCA Cathodes for Lithium-Ion Batteries.”