Transforming Waste into Energy: Toyota Chemical Engineering Pursues a Carbon-Free Future Through Garbage Incineration
In a groundbreaking development towards carbon neutrality, Toyota and Toyota Chemical Engineering have partnered to revolutionise the battery recycling process. The focus is on the "black mass," an intermediate material obtained by shredding used lithium batteries, which contains valuable metals such as lithium, cobalt, nickel, and copper embedded in the shredded battery electrodes.
The recycling process involves recovering these critical minerals from the black mass to reintroduce them into the supply chain, reducing the need for newly mined raw materials. This approach contributes significantly to carbon neutrality goals by minimising the environmental impact in the drive towards sustainable energy storage.
The black mass serves as the starting point for hydrometallurgical treatments, where aqueous chemical solutions extract and separate valuable metals with higher recovery rates and lower energy use compared to pyrometallurgical methods. Remarkably, advances have been made in directly purifying lithium from black mass, enabling the extraction of high-purity lithium compounds essential for battery manufacturing.
This test plant, the first of its kind, marks the initial step in transforming spent batteries into new ones using a method that safely recovers materials from spent car batteries without incineration. The batteries tested include nickel metal hydride batteries (NiMH), lithium-ion batteries used in other hybrid cars, and a lithium-ion battery from a bZ4X.
The electrolytic solution in the batteries allows for easier movement of positive and negative ions for charging and discharging electricity, but it is highly flammable. Current recycling methods often involve incinerating spent batteries and collecting the rare metals left over, which reduces the amount of materials recovered and releases a significant amount of CO2.
To eliminate the risk of fire, the facility can distil and extract the electrolytic fluid, a technique not used in conventional recycling. After the fluid is extracted, the cells are shredded and sorted, with large pieces containing aluminum and iron, and a powder called "black mass" containing rare metals recovered.
The sorted pieces and powders are then transported to cooperating companies and processed into materials for new batteries. This new recycling technology allows for sorting and recovering materials that cannot be obtained from conventional incineration, dramatically increasing recovery rates.
Toyota is committed to achieving incineration-free recycling of batteries, with the goal of reducing emissions throughout the lifecycle of the batteries, from manufacturing to decommissioning and recycling. In Europe, regulations requiring battery manufacturers to use a fixed ratio of rare metals recovered from spent batteries will take effect in 2031.
Keisuke Isomura, Assistant Manager of the Environment Affairs and Engineering Management Division, emphasised the importance of developing low-emission disposal methods for Toyota's goals of establishing a circular economy and achieving carbon neutrality. Kenichiro Muramatsu, from the Raw Material Development Division, stated that the new recycling technology is a significant step towards Toyota's ultimate goal of creating a circular economy, where garbage becomes a resource without emitting carbon.
Toyota Chemical Engineering is also working on developing various other technologies, such as making electricity from water and garbage, and industrial waste disposal using incineration without releasing CO2 into the atmosphere. Countries worldwide are promoting recycling to recover rare metals like cobalt, lithium, and nickel from spent batteries, making this innovative battery recycling process a significant contribution to global sustainability efforts.
- This new battery recycling technology, developed by Toyota and Toyota Chemical Engineering, is designed to recover critical minerals like lithium, cobalt, nickel, and copper from the "black mass," contributing to environmental science and the drive towards carbon neutrality in the industry.
- The recycled minerals can be reintroduced into the supply chain, thus reducing the need for financing new raw materials and energy consumption in the manufacturing of batteries, which is beneficial for businesses pursuing sustainable energy storage.
- The hydrometallurgical treatments in the recycling process, such as the extraction and separation of valuable metals, boast higher recovery rates and lower energy use compared to traditional pyrometallurgical methods, making it a more environmentally-friendly solution in the realm of financial and environmental-science aspects.
