UNIST and KIST develop high-capacity organic anode material for electric vehicle batteries

A material has been developed that can increase the charging speed of electric vehicle batteries while lowering costs.

Professor Kang Seok-joo of the Ulsan National Institute of Science and Technology (UNIST) and Director Ahn Seok-hun of the Korea Institute of Science and Technology (KIST) Jeonbuk branch functional composite materials research center announced on the 19th that they developed a high crystallinity organic anode material "Cl-cHBC" for lithium-ion batteries. The research results were published in the international journal "ACS Nano" on Jan. 21.

In winter, the diffusion speed of lithium ions in the anode of a battery decreases, causing a problem with the charging speed of electric vehicle batteries. Therefore, for cases where fast charging is needed, such as in electric buses, lithium titanate (LTO) material is used instead of graphite. However, LTO has the disadvantage of being half the capacity of graphite, having a lower voltage, and being more expensive.

The organic anode material Cl-cHBC developed by the research team is characterized by being 1.5 times larger in maximum capacity than the LTO material while also being cheaper and lighter. Existing organic materials had low crystallinity and required a high-temperature post-treatment process, but the research team was able to maintain high crystallinity at low temperatures by adding a less soluble solvent to crystallize the solute through a co-solvent process.

The new high-crystallinity anode material allows lithium ions to move quickly and has high electrical conductivity. This is because the higher the crystallinity, the straighter the path for ions and electrons to move. As a result, the charging speed has increased, and the battery lifespan has been extended.

The research team stated that when Cl-cHBC was combined with lithium iron phosphate (LFP) cathode material and tested, it showed performance with a discharge voltage of 3.0V, which is a 67% improvement compared to existing LTO. Until now, LFP batteries have been extensively used in electric vehicles due to their low cost, but they had the drawback of low output. However, this research confirmed the potential to enhance the performance of LFP batteries.

The joint researchers noted, "The developed material can be synthesized at low temperatures, so if it is commercialized, additional price competitiveness can be secured," adding, "Thanks to its lightweight and high output characteristics, applications in areas such as electric vehicles and drones are also expected."

References

ACS Nano (2025), DOI : https://doi.org/10.1021/acsnano.4c13561