With the rapid development of the new energy vehicle industry, the wave of retired lithium batteries has arrived. According to industry data, the number of retired lithium batteries in China will exceed 1 million tons in 2025, and environmental protection recycling has become a key link to ensure the sustainable development of the industrial chain. In this process, the grinder, as the core equipment in the preprocessing stage, is providing important support for the resource utilization and harmless treatment of lithium batteries with its unique functions.
In the lithium battery recycling process, the grinder undertakes the primary task of breaking battery components. Lithium batteries have a complex structure, including various components such as metal shells, electrode sheets, diaphragms, and electrolytes, and each component is closely combined. The grinder breaks the entire group or single battery into small pieces of 5-20mm through mechanical forces such as impact, shearing, and extrusion, initially separating the originally tightly combined components and laying the foundation for the subsequent separation of metal shells and electrode materials. For example, in the rough grinding stage, it can break the battery shell into regular fragments and the electrode sheet into strips with a base, facilitating the subsequent separation work.
Moreover, the grinder can also refine the material particle size and promote component homogenization. The initially crushed materials need to be further ground to a fine particle size of 100-300 meshes. This process can break the agglomeration state of electrode materials, make the positive active materials fall off from the aluminum foil base, and form dispersed particles. At the same time, it ensures the uniform particle size of the materials, avoids the problems of "over-processing" or "insufficient processing" during subsequent sorting or extraction, improves the consistency of material reactions, and provides raw materials with stable quality for subsequent processes.
The grinder also plays an important role in helping separate impurities from target components. By controlling the particle size, it strengthens the differences in physical properties of different components, facilitating efficient separation by subsequent sorting equipment. For instance, the steel/aluminum fragments of the battery shell, after being ground, become regular blocks, which can be separated from steel by magnetic separation or from aluminum and lightweight diaphragms by air separation using density differences; the diaphragm is a lightweight organic material, which becomes fine fibrous after grinding and can be separated from heavier electrode particles by air separation based on aerodynamic differences, greatly improving the efficiency of impurity separation.
The grinder can also significantly improve the subsequent extraction efficiency and reduce processing costs. For the wet recycling process, the fine-grained materials increase the specific surface area, making it easier for active materials to contact with leaching agents, shortening the leaching time, and the leaching rate of lithium can be increased from over 70% to over 90%; in pyrometallurgical smelting, uniform fine particles can reduce heat and mass transfer resistance at high temperatures, reduce energy consumption, and avoid local overburning or unreacted residues caused by uneven heating of large materials.
It is worth noting that modern grinding equipment, combined with environmental protection design, can effectively reduce the emission of pollutants. Lithium battery recycling needs to strictly control the pollution of electrolyte volatile substances and heavy metal dust. The grinder adopts a closed design, combined with a negative pressure dust removal system, which can collect the dust generated during the grinding process in a timely manner to avoid diffusion into the environment; volatile organic compounds are introduced into the waste gas treatment system through closed pipelines, meeting environmental protection emission standards and safeguarding environmental protection recycling.
Industry experts said that as the "material preprocessing hub" of lithium battery environmental protection recycling, the performance of the grinder directly affects the recycling efficiency, resource utilization rate, and environmental protection level. With the continuous upgrading of technology, grinding equipment will play a more important role in the lithium battery recycling industry chain, promoting the high-quality development of China's new energy industry towards a green and circular direction.