Electric vehicle charging times have been a concern, with standard charging taking about 10 hours or more, and fast-charging methods still requiring at least 30 minutes. This issue is compounded by the availability of charging stations. However, a recent breakthrough in battery technology could potentially address these challenges.
A research team led by Professor Won Bae Kim from Pohang University of Science and Technology has developed a new anode material for lithium-ion batteries, commonly used in electric vehicles. The team employed a unique self-hybridization method involving a galvanic replacement-derived process to synthesize manganese ferrites (Mn3-xFexO4) nanosheets.
By utilizing this groundbreaking technique, the storage capacity of the batteries was increased by approximately 1.5 times above the theoretical limit. Consequently, the charging time for electric vehicles could be reduced to as little as six minutes. The research findings were recognized for their excellence and published as a front cover paper in Advanced Functional Materials.
The team devised a novel approach to synthesize manganese ferrites, which are known for their exceptional lithium-ion storage capacity and ferromagnetic properties. Initially, a galvanic replacement reaction occurred in a solution of manganese oxide mixed with iron, resulting in a heterostructure compound with manganese oxide inside and iron oxide outside.
Subsequently, the researchers employed a hydrothermal method to produce nanometer-thick sheets of manganese ferrites with expanded surface areas. This approach effectively harnessed highly spin-polarized electrons, significantly enhancing the storage capacity for a larger quantity of lithium ions. The innovation allowed the team to surpass the theoretical capacity of the manganese ferrites anode material by over 50 percent.
The increased surface area of the anode material facilitated the movement of a larger number of lithium ions simultaneously, thereby enhancing the battery’s charging speed. Experimental results demonstrated that it only took six minutes to charge and discharge a battery with a capacity equivalent to those currently used in electric vehicles on the market. This study not only achieved a breakthrough in the theoretical capacity of the anode material but also substantially accelerated the battery charging process.
Professor Won Bae Kim, the driving force behind this research, expressed that their work offers new insights into overcoming electrochemical limitations associated with conventional anode materials. By applying rational design with surface alteration using electron spin, they were able to increase battery capacity. He expressed optimism that this development could lead to enhanced battery durability and reduced recharging time for electric vehicles.