Sorting Lithium-Ion Battery Electrode Materials Using Dielectrophoresis

Lithium-ion batteries (LIBs) are common in everyday lifeand thedemand for their raw materials is increasing. Additionally, spentLIBs should be recycled to achieve a circular economy and supply resourcesfor new LIBs or other products. Especially the recycling of the activematerial of the electrodes is the focus of current research. Existingapproaches for recycling (e.g., pyro-, hydrometallurgy, or flotation)still have their drawbacks, such as the loss of materials, generationof waste, or lack of selectivity. In this study, we test the behaviorof commercially available LiFePO4 and two types of graphitemicroparticles in a dielectrophoretic high-throughput filter. Dielectrophoresisis a volume-dependent electrokinetic force that is commonly used inmicrofluidics but recently also for applications that focus on enhancedthroughput. In our study, graphite particles show significantly highertrapping than LiFePO4 particles. The results indicate thatnearly pure fractions of LiFePO4 can be obtained with thistechnique from a mixture with graphite.

Automated summary

Lithium-ion batteries (LIBs) are widely used and their demand for raw materials is increasing. The recycling of spent LIBs is crucial to achieve a circular economy and provide resources for new LIBs or other products. However, current recycling methods have limitations. This study explores the behavior of LiFePO4 and graphite particles in a dielectrophoretic high-throughput filter and demonstrates the potential for obtaining pure LiFePO4 fractions from a mixture with graphite.