Recycling diesel soot nanoparticles for use as activated carbon in Li ion batteries

摘要

We report the successful capture and reuse of diesel exhaust soot particles as a conductive additive in lithium manganese oxide (LMO) and lithium iron phosphate (LFP) cathodes in Li-ion batteries. This approach enables an abundant toxic pollutant to be converted into a valuable material for energy storage devices. This study consists of an initial characterization of the diesel soot particles, a high-temperature annealing step to remove residual organics and unburned hydrocarbons, and characterization of the electrical performance in a Li-ion battery configuration. Here, composite electrodes are fabricated by mixing active materials (LFP or LMO) with conductive carbon and binders. The performance of the diesel soot particles as conductive additives is compared with that of commercially available activated carbon (i.e., Super P (R)). The current evolution of the composite electrode made with diesel soot particles demonstrates comparable performance to the electrodes containing the Super P (R) carbon. Based on high-resolution transmission electron microscope (HRTEM) images and scanning mobility particle sizer (SMPS) spectra, we find that these diesel soot nanoparticles follow a narrow log-normal distribution centered around 100 nm in diameter and consist of highly porous amorphous carbon, which provide a large surface-to-volume ratio, making them ideal candidates for electrode materials in Li ion batteries.