To increase the capacity and quicken the charging of lithium-ion batteries, Professor Won Bae Kim and his group at POSTECH use the electron spin of the anode material.
Prof. Won Bae Kim (left), Song Kyu Kang (center) and Minho Kim (right). Image Credit: Pohang University of Science and Technology
An electric vehicle typically requires 10 hours or more to fully charge, and even with fast-charging techniques, it takes at least 30 minutes, presuming a charging station location is available. The lack of EV charging outlets might be lessened if electric vehicles could be charged as quickly as gasoline-powered vehicles are refueled.
The ability of the anode material to hold lithium ions affects the efficiency of lithium-ion batteries, particularly those used in electric vehicles.
A research team to create a new anode material was recently led by Professor Won Bae Kim from the Department of Chemical Engineering and the Graduate Institute of Ferrous & Energy Materials Technology at Pohang University of Science and Technology.
His group, which also included Ph.D. candidates Song Kyu Kang and Minho Kim from the Department of Chemical Engineering, created manganese ferrites (Mn3-xFexO4) nanosheets utilizing a cutting-edge self-hybridization technique that utilized a simple galvanic replacement-derived procedure.
This ground-breaking method allows an electric vehicle to be charged in as little as six minutes while increasing storage capacity by around 1.5 times above the theoretical maximum. As a result of the research’s excellence, it was acknowledged and published as the front cover article in Advanced Functional Materials.
For the anode material used in this investigation, manganese ferrites, which have excellent ferromagnetic and lithium-ion storage capacities, were synthesized using a novel technique. First, a manganese oxide and iron solution underwent a galvanic replacement reaction, creating a heterostructure compound with manganese oxide inside and iron oxide outside.
The group also employed a hydrothermal technique to fabricate manganese ferrites sheets that were nanometer thick and had increased surface areas.
By using highly spin-polarized electrons, this method dramatically increased the ability to store a large number of lithium ions. This innovation helped the team was able to surpass the theoretical capacity of the manganese ferrites anode material by more than 50%.
The surface area of the anode material was increased, which accelerated the charging of the battery by enabling the simultaneous movement of a high number of lithium ions. According to the results of an experiment, a battery with a capacity similar to that found in the current generation of EVs could be charged and discharged in under six minutes.
To significantly accelerate battery charging and achieve a breakthrough in the theoretical capacity of the anode material, this study has improved the difficult synthesis process.
We have offered a new understanding on how to overcome the electrochemical limitations of conventional anode materials and increase battery capacity by applying the rational design with surface alteration using electron spin.
Won Bae Kim, Professor, Pohang University of Science and Technology
He expressed hope that this research would result in longer-lasting batteries and quicker charging times for electric vehicles.
The Mid-Career Researcher Program, Advanced Research Center Program of the National Research Foundation of Korea, Ministry of Science and ICT, Ministry of Trade, Industry and Energy Program to Upgrade the Performance of Next Generation Rechargeable Lithium-ion Batteries and Develop New Manufacturing Technologies provided funding for this study.