When sourcing LED solar lights, you must prioritize the Luminous Efficacy (lm/W), which indicates how efficiently the light converts power into brightness; look for at least 150lm/W. Additionally, evaluate the Battery Type, where Lithium Iron Phosphate (LiFePO4) is preferred over Lead-acid due to its 2,000+ charge cycles and better thermal stability. Ensure the Solar Panel Type is Monocrystalline Silicon, as it offers a higher conversion efficiency (up to 21%) compared to polycrystalline alternatives.