Electrochemical characteristics of two propylene carbonate-encapsulating polymer electrolytes based on a polyester of 3,3’-thiodipropionic acid and tri-ethylene glycol, and on a bis-amino poly(ethyleneoxide) PEG-poly (propyleneoxide) (PPO) copolymer, respectively, are compared to those of a polymer network based on PEO and a styrenic macromonomer of PEG, with particular emphasis on Li/polymer electrolyte interface stability.