[Science World] Overcoming Future Resource Wars with 'Black Powder' Treatment Technology

As electric vehicles become more widespread, the recycling market for used “waste batteries” is gaining attention. This is because waste batteries are regarded not as mere trash but as new resources. According to the report “Analysis of Raw Material Procurement Effectiveness in the Electric Vehicle Waste Battery Recycling Industry” published by the Korea Chamber of Commerce and Industry, by 2045, it is expected that 20,000 tons of lithium can be obtained through recycling electric vehicle waste batteries. This amount corresponds to 28% of South Korea’s lithium imports in 2022. Additionally, 21,000 tons of manganese, 22,000 tons of cobalt, and 98,000 tons of nickel can also be recovered.

How is waste battery recycling carried out? First, the waste batteries are crushed into powder, called “black powder.” The efficiency of the recycling process depends on how well this black powder is processed. Black powder is often even referred to as a new resource for the late 21st century.

Waste battery recycling technology can be divided into two types: wet and dry processes. The wet process chemically dissolves the black powder to extract various resources such as lithium, graphite, nickel, cobalt, and manganese. While this method allows for the recovery of valuable resources like lithium without discarding them, it is complex and costly.

The dry process requires no pretreatment. In other words, black powder is not produced. Instead, waste batteries are melted directly in a blast furnace to form alloy lumps, which are then smelted again to extract metals such as nickel, cobalt, copper, and iron. This method is simple and fast but requires a lot of energy, and operating the blast furnace consumes significant energy as well.

Above all, lithium cannot be recovered through the dry process. Lithium is one of the most precious resources used in battery manufacturing. However, if the slag or dust?byproducts discharged during the dry process?are collected and subjected to the wet process from the beginning, lithium can be extracted. But since this means repeating the process twice, the efficiency decreases.

Of course, the dry process has its advantages. The process is simple, and multiple resources can be recycled simultaneously. Conversely, the wet process can recycle all various resources without discarding any, but the procedure is complicated and labor-intensive.

Methods to simplify the wet process are also being developed. When extracting N·C·M (nickel, cobalt, manganese), which are frequently used materials in batteries, the conventional method required dissolving these three metals in three separate steps. However, the latest method can dissolve all three substances at once. The reason this was not done previously was the difficulty in adjusting the composition ratio of the materials dissolved simultaneously. Recently, it has become possible to produce alloys with the desired ratio directly, attracting significant interest from domestic and international companies.

The scientific community is also active. In May last year, the Institute for Basic Science developed a technology that can separate and extract metals such as lithium, nickel, cobalt, and manganese from waste batteries in a single process, drawing attention. The Korea Institute of Geoscience and Mineral Resources also developed a technology in 2022 that can extract lithium, nickel, cobalt, and manganese in one process.

According to industry experts, more than 50% of battery raw materials are expected to be supplied through recycling processes after 2050. In other words, battery recycling technology can be regarded as a core foundational technology necessary to sustain future society. This is why full efforts must be made toward technology development and market preemption.

Jeon Seung-min, Science and Technology Specialist Writer / Editor-in-Chief of Popular Science