Hollow Cage Evaporator With Thermal and Convection Regulation: Rotation‐Driven Salt Self‐Cleaning for Synergistic Water–Lithium Recovery

ABSTRACT Lithium extraction from brines is limited by severe ion interference and interior performance of conventional separation technologies. Existing solar evaporators also suffer from insufficient salt resistance, low mass transfer efficiency and poor lithium selectivity, which restricts the simultaneous high‐efficiency production of freshwater and lithium recovery. Herein, a hollow cage‐like dynamic evaporator @ACRC–10 is fabricated. Its hollow structure optimizes vapor diffusion in large‐scale evaporation. The elliptical bearing enables radiant light regulation and interfacial thermal management, and the curved structure achieves directional water transport and localized salt crystallization. Driven by salt crystal gravity, the evaporator realizes autonomous salt shedding, active self‐cleaning, and efficient salt resource utilization. Outdoor tests demonstrate an evaporation rate of 2.48 kg m −2 h −1 , a lithium adsorption capacity of 65.62 mg g −1 , a Li/Mg separation factor of 139.61, and a steady daily water yield of 25 L m −2 over 32 days of continuous operation. This integrated system addresses the single functional drawbacks of conventional technologies, providing an effective strategy for green lithium extraction and freshwater recovery from brine.