End-of-life EV batteries can be recycled to look like new [K-Tech in Science]

[Financial News] An eco-friendly technology has been developed that can recycle end-of-life batteries while reducing wastewater containing heavy metals. According to the Korea Institute of Energy Research (KIER) on the 27th, a research team led by Dr. Woo Joong-je at KIER's Gwangju Eco-Friendly Energy Research Center developed a solution-based process that solves the challenge of separating current collectors, long seen as a major obstacle to direct recycling of used batteries, while also regenerating spent cathode materials to near-new quality.
The researchers focused on direct recycling, a method that restores cathode materials while preserving the battery structure as much as possible. The key was to remove the current collector, which is strongly attached to the cathode material, without causing damage. The team used diethylene glycol. When spent cathode material is immersed in a diethylene glycol solution and heated to 130 degrees Celsius, an oxidation reaction produces glycolaldehyde. The substance weakens the adhesion between the cathode material and the current collector, allowing the collector to be separated effectively.
Performance was also restored to nearly the same level as new materials. NCM cathode material, which is widely used in electric vehicles, reached 99.1% of the capacity of a new product, while LFP Cathode Material reached 99.7%.
When degraded cathode material taken from a 50Ah battery for electric vehicles was restored and applied to a small test cell, discharge capacity increased from 30.6mAh to 34.6mAh. This confirms the technology's potential for practical use in recycling end-of-life EV batteries, beyond the laboratory stage.
Song Jin-ju, a researcher at KIER who led the study, said, "Because spent battery cathode material can be recycled without dissolving it, we can reduce environmental pollution caused by wastewater and also cut the energy used in the process." She added, "The process is simple and does not require a separate sealed environment, so it has very high potential for industrial application."
Previously, wastewater generated during conventional recycling of end-of-life EV batteries could contain heavy metals, raising concerns that improper treatment could lead to soil and groundwater contamination. In particular, cathode materials that determine battery capacity contain expensive rare metals such as cobalt, making it important to secure technologies that can efficiently recover and reuse them.
The findings were published in the September issue of the international journal Advanced Science.

[email protected] Yeon Ji-an Reporter