A team of scientists from Oak Ridge National Laboratory is using the precision of an electron beam to instantly adhere cathode coatings for lithium-ion batteries. This new development, as reported in the Journal of The Electrochemical Society, could lead to a leap in efficiency that saves energy, reduces production cost, and eliminates the use of toxic solvents.

This from ORNL:

The technique uses an electron beam to cure coating material as it rolls down the production line, creating instantaneous cross-links between molecules that bind the coating to a foil substrate, without the need for solvents, in less than a second.

Read the full article.

“Typical curing processes can require drying machinery the length of a football field and expensive equipment for solvent recovery,” says David Wood, co-author of the study. “This approach presents a promising avenue for fast, energy-efficient manufacturing of high-performance, low-cost lithium-ion batteries.”

Read the full paper, “Electron Beam Curing of Composite Positive Electrode for Li-Ion Battery.”

Image: ANL/Flickr

A new open access paper published in the Journal of The Electrochemical Society entitled, “Lithium-Ion Cathode/Coating Pairs for Transition Metal Containment,” finds a new cathode coating for li-ion batteries that could extend the technology’s lifespan.

According to Green Car Congress, the dissolution of transition metals is a major contributor to a li-ion battery’s expedited aging and degradation. However, this new study published in JES by ECS members David Snydacker, Muratahan Aykol, Scott Kirklin, and Christopher Wolverton from Northwestern University makes the case for a new, promising candidate that can act as a stable coating and limit the dissolution of transition metals into the lion electrolyte. That candidate is Li₃PO₄.

This from “Lithium-Ion Cathode/Coating Pairs for Transition Metal Containment”:

There are several distinct categories of strategies for limiting TM dissolution from the cathode. Electrolytes can be tailored to reduce reactivity with the cathode. Cathode materials can be doped to control the oxidation states of transition metals. This doping can be applied to the entire cathode particle or just near the surface. Cathode materials can also be covered with surface coatings to limit TM dissolution. Surface coatings can perform a variety of functions for different cathode materials. In this work, we evaluate the ability of coating materials to contain TMs in the cathode and thereby prevent TM dissolution into the electrolyte.

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Cathode particles treated with the carbon dioxide-based mixture show oxygen vacancies on the surface.
Image: Laboratory for Energy Storage and Conversion, UC San Diego

An international team of researchers has recently demonstrated a 30 to 40 percent increase in the energy storage capabilities of cathode materials.

The team, led by ECS member and 2016 Charles W. Tobias Young Investigator Award winner, Shirley Meng, has successfully treated lithium-rich cathode particles with a carbon dioxide-based gas mixture. This process introduced oxygen vacancies on the surface of the material, allowing for a huge boost to the amount of energy stored per unit mass and proving that oxygen plays a significant role in battery performance.

This greater understanding and improvement in the science behind the battery materials could accelerate developments in battery performance, specifically in applications such as electric vehicles.

(READ: “Gas-solid interfacial modification of oxygen activity in layered oxide cathodes for lithium-ion batteries“)

“We’ve uncovered a new mechanism at play in this class of lithium-rich cathode materials,” says Meng, past guest editor of JES Focus Issue on Intercalation Compounds for Rechargeable Batteries. “With this study, we want to open a new pathway to explore more battery materials in which we can control oxygen activity.”

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