Slowing the dendrite formation process is one way to alleviate the fast capacity fade and safety issues in lithium metal battery systems. We used tetraethylene glycol dimethyl ether (TEGDME) as a complementary solvent to increase the desolvation activation energy of Li⁺, reduce the speed of lithium electrodeposition kinetics, and suppress dendrite formation. Density functional theory calculations combined with Raman spectroscopy indicate that a stronger coordination interaction is obtained between Li⁺ and TEGDME than between Li⁺ and 1,2-dimethoxyethane (DME) or 1,3-dioxolane (DOL). Such a strong coordination leads to a slower electrochemical reaction rate. As a result, uniform lithium electrodeposition morphology and good cycling stability of a Li|Li symmetric cell for more than 500 hours were achieved. Our approach suggests a way in which dendrite formation can be controlled by the electrochemical reaction itself.