Composite polymer electrolytes characteristics

In view of the many parameters involved viz. blend composition, types of plasticizer, and nano-fillers, grain size, and dispersion and so on, an in-depth study of the conductivity mechanism of the electrolyte system and an understanding of the characteristic and behavior of each additive are important in the pursuit of an appUcable PEO/PMMA composite polymer electrolyte system. 

Subban, R.H.Y. and Arof, A.K. (2004) Charge-discharge characteristics of LiCo02/mesocarbon microbeads battery with poly(vinyl chloride)-based composite polymer electrolyte. /. Power Sources, 134,211-221. 

The current challenge for PEMFC is to raise the working temperature above 80 °C. Composite membranes are a potential solution. The addition of inorganic fillers induces important improvements in water retention at high temperature, conductivity, cell resistivity, mechanical properties, etc. These improvements are related to filler concentration, structure and size, interfaces, polymer matrix and membrane characteristics. It is difficult to compare these ionomer/fiUer composites because their performances depend on the electrolyte preparation and testing conditions (RH, temperature, etc.). H2/02(air) cells based on composite polymer electrolytes have been successfully operated at temperatures up to 120 °C under ambient pressure, and up to 150 °C under pressures of 3-5 atm, but more research... 

Shim, J., Ha, H. Y., Hong, S. and Oh, I. 2002. Characteristics of the Nation ion-omer-impregnated composite membrane for polymer electrolyte fuel cells. Journal of Power Sources 109 412-417. 

Cho E.A., Jeon U.-S., Fla H.Y., Hong S.-A., Oh I.-H. Characteristics of composite bipolar plates for polymer electrolyte membrane fuel cells. Journal of Power Sourses 125 (2004) 178-182. 

A. Yoshizawa, M. Takeda, Y. Oura, Y. Takemoto and K. Naoi, Low-molecular-weight soluble polyaniline for electrolytic capacitor, Electrochemistry, 1999, 67, 45 H. Yamamoto, K. Kanemoto, M. Oshima and I. Isa, Self-healing characteristics of solid electrolytic capacitor with polypyrrole electrolyte, Electrochemistry, 1999, 67, 855 M. Mastragostino, R. Paraventi and A. Zanelli, Supercapacitors based on composite polymer electrodes, J. Electrochem. Soc., 2000,147, 3167. 

Zhang, X., Wang, C., Appleby, A., Little, F. 2002. Characteristics of lithium ion-conducting composite polymer-glass secondary cell electrolytes. 

Transient absorption spectroscopy was employed to study electron-transfer dynamics in solar cells incorporating the polymer electrolyte based on EO copolymers with and without plasticizer. Electron-transfer kinetics were collected as a function of electrolyte composition, white light illumination, and device voltage.The results were further correlated with the current/ voltage characteristics of the solar cells. There are two main recombination pathways which can cause loss in DSSC efficiency electrons injected into the T102 conduction band can recombine with either dye cations or with the redox electrolyte (equations 10.8 and 10.9, respectively). 

The speed of p- and n-type doping and that of p-n junction formation depend on the ionic conductivity of the solid electrolyte. Because of the generally nonpolar characteristics of luminescent polymers like PPV, and the polar characteristics of solid electrolytes, the two components within the electroactive layer will phase separate. Thus, the speed of the electrochemical doping and the local densities of electrochemically generated p- and n-type carriers will depend on the diffusion of the counterions from the electrolyte into the luminescent semiconducting polymer. As a result, the response time and the characteristic performance of the LEC device will highly depend on the ionic conductivity of the solid electrolyte and the morphology and microstructure of the composite. 

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