Recycling Spent Lithium-Ion Batteries Using Waste Benzene-Containing Plastics: Synergetic Thermal Reduction and...

Spent lithium-ion batteries (LIBs) and benzene-containing polymers (BCPs) are two major pollutants that cause serious environmental burdens. Herein, spent LIBs and BCPs are copyrolyzed in a sealed reactor to generate Li₂CO₃, metals, and/or metal oxides without emitting toxic benzene-based gases. The use of a closed reactor allows the sufficient reduction reaction between the BCP-derived polycyclic aromatic hydrocarbon (PAH) gases and lithium transition metal oxides, achieving the Li recovery efficiencies of 98.3, 99.9, and 97.5% for LiCoO₂, LiMn₂O₄, and LiNi_0.6Co_0.2Mn_0.2O₂, respectively. More importantly, the thermal decomposition of PAHs (e.g., phenol and benzene) is further catalyzed by the in situ generated Co, Ni, and MnO₂ particles, which forms metal/carbon composites and thus prevent the emissions of toxic gases. Overall, the copyrolysis in a closed system paves a green way to synergistically recycle spent LIBs and handle waste BCPs.