Lead halide perovskite light-emitting diodes (PeLEDs) have emerged as highly promising candidates for next-generation displays and solid-state lighting, achieving record-high external quantum efficiencies (EQEs) exceeding 30%. The perovskites possess outstanding optoelectronic properties, such as high photoluminescence quantum yields (PLQY), narrow full-width at half maximum (FWHM), and efficient radiative recombination, driven fundamentally by the unique Pb2+ orbital configuration that imparts direct bandgaps and intrinsic defect tolerance. However, commercializing PeLEDs in next-generation displays and lighting is bottlenecked by dual-challenges in material and device: intrinsically, the soft lattice stemming from ionic soft lattice is prone to phase degradation, ion migration, and environment-induced dissociation, triggering severe non-radiative recombination, luminescence failure and environmental toxicity; extrinsically, unbalanced carrier injection, interfacial energy-level mismatch, and Joule heating effect jointly inflict low luminescence efficiency and rapid device decay. This review offers a systematic overview of multi-dimensional strategies developed to resolve this key contradiction. From a synthetic chemistry perspective, we summarize intrinsic lattice stabilization via compositional engineering, surficial ligand passivation and core-shell heterostructures, as well as solvent-free mechano-synthesis pathways. From a device engineering standpoint, we highlight charge-transport layer optimization, self-assembled monolayer (SAM) functionalization for interfacial-defect passivation and balanced carrier injection, alongside photonic waveguiding management. Finally, we discuss future perspectives on atomic-level mechanism characterization, ligand-mediated surface reconstruction, and closed-loop lifecycle management, offering a comprehensive roadmap toward the high-performance, long-term stability and scalable commercialization of next-generation PeLEDs for display and lighting technologies.