Multiple H-Bonding Cross-Linked Supramolecular Solid-Solid Phase Change Materials for Thermal Energy Storage and Management

Solid-solid phase change materials (SSPCMs) are considered among the most promising candidates for thermal energy storage and management. However, the application of SSPCMs is consistently hindered by the canonical trade-off between high TES capacity and mechanical robustness. In addition, they suffer from poor recyclability due to chemical cross-linking. Herein, a straightforward but effective strategy for fabricating supramolecular SSPCMs with high latent heat and mechanical strength is proposed. The supramolecular polymer employs multiple H-bonding interactions as robust physical cross-links. This enables SSPCM with a high enthalpy of phase transition (142.5 J g-1), strong mechanical strength (36.9 MPa), and sound shape stability (maintaining shape integrity at 120 degrees C) even with a high content of phase change component (97 wt%). When SSPCM is utilized to regulate the operating temperature of lithium-ion batteries, it significantly diminishes the battery working temperature by 23 degrees C at a discharge rate of 3 C. The robust thermal management capability enabled through solid-solid phase change provides practical opportunities for applications in fast discharging and high-power batteries. Overall, this study presents a feasible strategy for designing linear SSPCMs with high latent heat and exceptional mechanical strength for thermal management. A supramolecular polymeric solid-solid phase change material with high latent heat storage and superior mechanical strength is developed for thermal energy storage (TES and management through the construction of multiple H-bonding interactions within the polymer. This study provides new guidance for combining high TES density, robust mechanical properties, and sound thermal stability in one material.image