Hybrid gel electrolytes

WALKOWIAK, M., ZALEWSKA, A., JESIONOWSKI, T., WASZAK, D. and CZAJKA, B., 2006. Effect of chemically modified silicas on the properties of hybrid gel electrolyte for Li-ion batteries. Journal of Power Sources, 159(1), 449-453. 

DI NOTO V, VITTADELLO M, GREENBAUM S G, SUAREZ S, KANO K, FURUKAWA T (2004b), A new class of Uthium hybrid gel electrolyte systems , / Phys Chem B, 108, 18832-18844. 

In any case, it is perceived from the above discussion that the problem of longterm chemical stability of polycrystalline semiconductor liquid junction solar cells is far from being solved. Still, as already pointed out in the early research, any practical photovoltaic and PEC device would have to be based on polycrystalline photoelectrodes. Novel approaches mostly involving specially designed PEC systems with alternative solid or gel electrolytes and, most importantly, hybrid/sensitized electrodes with properties dictated by nanophase structuring - to be discussed at the end of this chapter - promise new advances in the field. 

The solid polymer electrolyte approach provides enhanced safety, but the poor ambient temperature conductivity excludes their use for battery applications. which require good ambient temperature performance. In contrast, the liquid lithium-ion technology provides better performance over a wider temperature range, but electrolyte leakage remains a constant risk. Midway between the solid polymer electrolyte and the liquid electrolyte is the hybrid polymer electrolyte concept leading to the so-called gel polymer lithium-ion batteries. Gel electrolyte is a two-component system, viz., a polymer matrix... 

On the other hand, we have reported the preparation of gel-type polymer electrolytes using polyether/salt hybrid oligomers [12]. A network-type PPO film was swollen with the PPO/triiluoromethylsulfonamide Uthium salt hybrid. The obtained gel containing 50 wt% of PPO/salt hybrid showed a low Tg of —62°C. The PPO/salt hybrid behaved as not only an added salt but also a plasticizer. The ionic conductivity was over 10 S cm at room temperature. Furthermore this gel electrolyte showed a favorable lithium-ion transference number of 0.7-0.8. 

However, it seems likely that a conductivity value of 10 S cm at room temperature is a goal that can only be achieved with polymer networks including organic solvents as plasticizers [96] or with polymer matrixes like polyacrylonitrile [97] or poly(methyl methacrylate) [98] entrapping a large amount of organic electrolytic solution, i.e., with hybrid and/or gel electrolytes. These electrolytes combine the advantage of the polymer s mechanical properties with the electrochemical properties of the liquid electrolytes. 

The strategy of hybrid and gel electrolytes is very promising for lithium-ion batteries, but it seems less viable for lithium-metal batteries due to the reactivity of lithium metal with the encapsulated solvent. In fact, high conductivity is not the only parameter in selecting a successful polymer electrolyte for the development of lithium batteries a low interface resistance and a high interface stability over time are also required to assure good cyclability and long life. 

Preparation of a Gel Electrolyte for a Hybrid Electrochromic Device Application... 

PAN-based gel electrolytes have been widely investigated as the plasticizer and salt components are molecularly dispersed to form homogenous, hybrid electrolyte films. The PAN in the gel electrolyte is deemed to mainly act as an encapsulating matrix material. PAN-based... 

Yamazaki S, Takegawa A, Kaneko Y, Kadokawa J, Yamagata M, Ishikawa M (2009) An acidic cellulose-chitin hybrid gel as novel electrolyte for an electric double layer capacitor. Electrochem Commun 11 68-70... 

In addition to the previous architectures, two more alternatives are possible for the structure of an electrochromic device (1) the solution configuration, including an electrochemical cell having an electrochromic material (or two) dissolved in a liquid or gel electrolyte (Figure 20.7b), and (2) the hybrid... 

G.B. Appetecchi, F. Alessandrini, S. Passerini, G. C ticcio, B. Boutevin, F. Guida-RetraSanta, Novel polymeric systems for lithium ion batteries gel electrolytes II. Hybrid cross-linked poly (fluorosilicone-ethyleneoxide), Electro-chimica Acta 50 (22) (2005) 4396-4404. 

Principally there are two classes of materials which can be used as a sol-gel electrolyte The first one is based on the fabrication of an inorganic oxide material (e.g., Ta20s, Nb20s) and the other on the preparation of organic-inorganic hybrids which combine the better conductive properties of polymer type material with the better mechanical strength of inorganic material. 

Kurc, B. 2014. Gel electrolytes based on poly(acrylonitrile)/sulpholane with hybrid Ti02/Si02 filler for advanced lithium polymer batteries. Electrochim. Acta 125 415-420. 

A. Banerjee, M. K. Ravikumar, A. Jalajakshi, P. Suresh Kumar, S. A. Gaffoor and A. K. Shukla, Substrate-integrated lead-carbon hybrid ultracapacitor with flooded, absorbent glass mat and silica-gel electrolyte configurations, J. Chem. Sci. 124,2012, 747-762. 

The same configuration of the hybrid Pb02/MHj. secondary battery has been applied with gel electrolytes instead of aqueous electrolyte (cf. Sections 11.7 and 11.9.1) [56] to solve some issues on conventional batteries maintenance cost and acid stratification for the lead-acid battery, high self-discharge and short life cycles for high current discharge for nickel-metal hydride battery. In addition, gel electrolytes offer advantages such as leak proof, maintenance-free and corrosion-free. 

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