Oak Ridge National Laboratory researchers have developed a new family of cathodes with the potential to replace the costly cobalt-based cathodes typically found in today’s lithium-ion batteries that power electric vehicles and consumer electronics.
The new class called NFA, which stands for nickel-, iron- and aluminum-based cathode, is a derivative of lithium nickelate and can be used to make the positive electrode of a lithium-ion battery. These novel cathodes are designed to be fast charging, energy dense, cost effective, and longer-lasting.
With the rise in the production of portable electronics and electric vehicles throughout the world, lithium-ion batteries are in high demand. According to Ilias Belharouak, ORNL’s scientist leading the NFA research and development, more than 100 million electric vehicles are anticipated to be on the road by 2030. Cobalt is a metal currently needed for the cathode which makes up the significant portion of a lithium-ion battery’s cost.
Advanced Materials – Lithium Iron Aluminum Nickelate, LiNixFeyAlzO2—New Sustainable Cathodes for Next‐Generation Cobalt‐Free Li‐Ion Batteries
In recent years, cobalt has become a critical constraint on the supply chain of the Li‐ion battery industry. With the ever‐increasing projections for electric vehicles, the dependency of current Li‐ion batteries on the ever‐fluctuating cobalt prices poses serious environmental and sustainability issues. To address these challenges, a new class of cobalt‐free materials with general formula of LiNixFeyAlzO2 (x + y + z = 1), termed as the lithium iron aluminum nickelate (NFA) class of cathodes, is introduced. These cobalt‐free materials are synthesized using the sol–gel process to explore their compositional landscape by varying aluminum and iron. These NFA variants are characterized using electron microscopy, neutron and X‐ray diffraction, and Mössbauer and X‐ray photoelectron spectroscopy to investigate their morphological, physical, and crystal‐structure properties. Operando experiments by X‐ray diffraction, Mössbauer spectroscopy, and galvanostatic intermittent titration have been also used to study the crystallographic transitions, electrochemical activity, and Li‐ion diffusivity upon lithium removal and uptake in the NFA cathodes. NFA compositions yield specific capacities of ≈200 mAh g−1, demonstrating reasonable rate capability and cycling stability with ≈80% capacity retention after 100 charge/discharge cycles. While this is an early stage of research, the potential that these cathodes could have as viable candidates in next‐generation cobalt‐free lithium‐ion batteries is highlighted here.
SOURCES- Advanced Materials, ORNL
Written By Brian Wang, Nextbigfuture.com