<p>The rapid growth of wind power, photovoltaics, and electric vehicles has led to the simultaneous accumulation of waste wind turbine blades (WTBs), retired photovoltaic modules (PVMs), and spent lithium-ion batteries (LIBs). However, existing recycling studies mainly focus on the separation and recovery of individual waste streams, while the potential reaction coupling among different new-energy wastes remains insufficiently explored. In this study, a waste-to-waste synergistic pyrolysis–reduction route was developed, in which pyrolysis gases generated from WTBs and PVMs were directly used as in situ reductants for roasting spent LIBs black mass. The pyrolysis behavior of WTBs and PVMs demonstrated their strong capacity to generate reducing gases. For EVA in PVMs, the solid residue decreased from 81.77% to 1.25% with increasing temperature, while the gas yield increased to 42.65%. For WTBs, an organic removal efficiency of 84.76% was achieved under air at 600 ℃, with CH₄ accounting for 63.4% of the pyrolysis gas. These reducing gases promoted the structural reconstruction of layered NCM cathode materials, enabling Li migration and conversion into water-leachable Li₂CO₃, while Ni and Co were mainly reduced to metallic phases and Mn was stabilized as MnO. Under the optimized conditions of 600 ℃, 90&#xa0;min, and a black mass-to-pyrolysis feedstock ratio of 1:1.5, the Li leaching efficiency reached 57.4%, whereas the leaching efficiencies of Ni, Co, and Mn remained below 0.05%. Combined with the first-stage lithium recovery, the overall lithium recovery reached 97.37%. In addition, glass fibers and porous pyrolytic carbon were recovered as value-added co-products. This work reveals the functional coupling between polymer-rich new-energy wastes and spent LIBs black mass, providing a new route for selective lithium recovery and multi-waste resource valorization.</p>