Ionic conductivity Future directions

The potential improvements that ionic liquids may impart to conducting polymers have been widely discussed - increased doping levels, smoother films, increased conductivity, decreased over-oxidation and improved electrochemical stability and so on. However, the research to date in this area has only just begun to investigate these hypotheses and demonstrate any material advantages in the use of ionic liquids future directions in this area must focus on some of these issues in addition to simply demonstrating the use of new ionic liquids for conducting polymer synthesis. 

The power density (W/kg or W/L) is also an important criterion, since the batteries will be subject to peaks in electricity production (charge) or consumption (discharge) for some future applications, such as storage of renewable forms of energy. In this case, it is the considerations of kinetics that are important. The insertion/extraction of the lithium into the material, which is directly linked to the active material s electronic and ionic conductivity, should be as rapid as possible. There also the problem is more complex because the kinetically limiting stage can be situated at the level of the interface between the active material and the electrolyte, as we will see next. 

We expect that the development of anisotropic materials that conduct ions in a desired direction as next-generation nanomaterials for devices to transmit energy and information or as molecular switches will continue. By using the dynamic ordered stmcture of hquid crystals to control the orientation, such materials could also act to control the aggregation state of the ions themselves. In the future, it should be possible to achieve selective transport, high ionic conductivity, and high anisotropy of target ions [188]. 

Due to the reduced number of charge carriers, Lh ions and anions have a high capability to form ion pairs. Therefore, the ionic conductivity of a single ion polymer electrolyte is lower than that of double ion polymer electrolytes. To facilitate dissociation and increase the ionic conductivity, major future improvements are expected to lie in the following directions ... 

As discussed in this entry, a number of novel materials and composites have been proposed as potential anodes for direct hydrocarbon solid oxide fuel cells. While many are promising, a commercially viable solution has not yet been found. The discusskm in this entry is deliberately framed arotmd the cxmcepts of ionic and electronic conductivity, electrocatalysis, and stability. It is essential for future researchers to address all of these topics when discussing new materials. The schematic in Fig. 3.4 represents both the complexity of the problem and the simpUcity that could potentially be achieved if a material meeting all of these requirements can be found. 

The subject matter was organized into four broad areas (a) Theories of Liquid Structures, (b) Ionic and Electronic Processes, (c) Interfacial Phenomena, and (d) Breakdown and Conduction. These four areas covered the bulk of the Institute. In addition, results of current research were presented in two Poster Sessions, and Future Research Directions and technological innovations derived from liquid-phase studies were discussed in a special session. 

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