Domestic researchers have developed a technology that reduces the charging time of electric vehicle batteries to 15 minutes.
Professor Choi Nam-soon of the Korea Advanced Institute of Science and Technology (KAIST) and his research team, in collaboration with Professor Hong Seung-beom's research team from the KAIST Department of Materials Science and Engineering, announced on the 17th that they have developed a new electrolyte technology that can dramatically shorten the charging speed of electric vehicle batteries. This research was published on the 11th in the international journal Advanced Materials.
As the adoption of electric vehicles expands, increasing battery charging speed is a key challenge for the industry. The currently used lithium-ion batteries employ ethylene carbonate-based electrolytes, but this electrolyte is highly viscous, causing lithium ions to move inefficiently. Additionally, a thick interfacial layer that forms on the surface of the anode hinders fast charging, while the accumulation of metallic lithium on the anode during charging reduces battery lifespan and increases fire risk.
To address this issue, the research team utilized a new electrolyte solvent, isobutyronitrile (isoBN), which can replace ethylene carbonate. The isoBN solvent has a viscosity that is 55% lower than that of the existing ethylene carbonate electrolyte, while its ionic conductivity is 54% higher, optimizing the movement of lithium ions within the battery.
The research team found that batteries using the isoBN electrolyte could be fast-charged within 15 minutes and maintained a high capacity retention rate of 94.2% after 300 charge/discharge cycles. In particular, it was demonstrated that during the charging process, lithium did not accumulate on the anode surface, addressing the issue of reduced battery lifespan.
Additionally, the research team succeeded in visualizing the movement of lithium ions for the first time in the world using atomic force microscopy. This clarified the impact of electrolyte composition on the internal structure and performance of the battery.
This research is regarded as a technology that dramatically reduces the long charging times, which was the biggest disadvantage of electric vehicle batteries, while also resolving battery lifespan issues. Furthermore, the isoBN solvent is expected to operate stably even in extremely low temperatures of minus 10 degrees Celsius, enabling smooth battery use in frigid regions.
Professor Choi Nam-soon noted, "This research has made progress in accelerating the popularization of electric vehicles due to the shortening of charging times with the nitrile-based electrolyte technology (isoBN) that overcomes the limitations of existing electrolyte materials," adding, "In the future, the fast charging technology of lithium-ion batteries is expected to be practical in various fields, including energy storage systems (ESS), drones, and the aerospace industry."
References
Advanced Materials (2025), DOI : https://doi.org/10.1002/adma.202418773