Kinetics and mechanisms for the electrodeposition of lithium from liquid and solid polymer electrolytes formed from lithium salts or from lithium salt complexes have been studied using chronoamperometric and cyclic voltammetric methods at a microelectrode. The type of nucleation and crystal growth process was determined as a function of polymer electrolyte composition. Exchange current densities, coulombic stripping efficiencies and lithium corrosion rates were evaluated.