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The focus of this research is to develop novel polymer gel electrolytes that overcome the drawbacks of conventional polymer electrolytes involving aqueous solvents or small organic molecules. In order to reach this aim, a series of novel polymer gel electrolytes were developed using crosslinked polymer matrix as a physical container acting to form cage around electrolytes. This structure leads to high ion conductivity under the applied electric field while maintaining mechanical integrity. The following gel electrolytes were prepared by varying the polymer hosts and type of electrolytes. The ion gels based on free radical polymerization of methylacrylate (MMA) in ionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) were transparent, self-standing and flexible with high ambient ionic conductivity in the range of 10-4~ 10-3 S/cm. The coupling effects between PMMA matrix and IL decrease with increasing the concentration of IL. The temperature dependence of ion conductivity followed Arrhenius Law, indicating a thermally activated ionic motion. Therefore, the high conductivity is considered to be due to the movement from both cations and anions to electrodes and weak polymer-ion interaction. Based on its high ion conductivity, the three layer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT/PSS) coated electroactive actuators were also developed, which exhibited a bending behavior under electrical field.The lithium polymer gels based on PMMA and modified siloxane (PEMPS) with LiTFSI exhibited transparency, flexibility and mechanical integrity, and remained miscible under all use conditions. This gel showed an ion conductivity 10-4 S/cm at 70 °C. The conductivity showed a maximum when the salt concentration increased for the composition of MMA/PEMPS = 30/70 and 40/60. At low concentration regime of solvent/salt (PEMPS/LiTFSI), the conductivity showed an increase with salt (LiTFSI) concentration. Beyond a critical salt concentration, the viscosity of the medium became high and this led to decrease of diffusion of ions in the medium and the decrease of conductivity. The conductivity was also increased with the decrease of PMMA/electrolyte ratio. The swelling ratio of PMMA network was also found to exhibit a maximum as the salt concentration increased. The swelling ratio increased as the PMMA/electrolyte ratio was decreased. The FTIR study indicates lithium salt was mostly dissociated by PEMPS, and had little interaction with PMMA polymer hosts. At last, polyvinyl alcohol (PVA)/KOH and polyacrylic acid (PAA)/KOH based aqueous gels were studied for the application in Ni-Zn batteries. The crystallization and chain entanglements formed physical crosslink for the PVA/KOH gel, while the copolymerization between acrylic acid and crosslinking agent formed the chemical crosslink for the PAA/KOH based gel. Both gels showed high ambient ion conductivity around 10-2 S/cm, satisfying the mechanical and ion conductivity requirements of the membrane for successful construction of Ni-Zn batteries.