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The work examines a total company operation for a specific range of newgeneration, polypropylene capacitors, which results in recommendations for future operational improvements and the installation of a new system of manufacture. The research covers the major facets of a business operation and their interdependency. These are, principally, corporate strategy, markets, product technology and manufacturing organisation. A major feature of the work was the successful installation of manufacturing and control systems based on cellular layout. As the production methods were predominantly assembly orientated, this represented a unique application of Group Technology (G.T.), in view of the fact that such areas had received little attention by academics and industrial engineers. The writer was fully responsible for all facets of installation and operation of the new system which involved gaining the co-operation of operators and staff, planning the physical movement of machines and other facilities, and the monitoring of working procedures at the post-installation stage. The overall conclusion was reached that the company had a fundamental strategic problem and that basic decisions were needed if polypropylene capacitors were to have a future. The work covered in this thesis provides a framework to aid this decision making process. The information presented on markets provides an indication of the scope available to the business, and the product technology section demonstrates the need for management of change such that minimum cost and market criteria can be met in capacitor design. The Group Technology work was also useful in this connection as the rationalised nature of flow and inputs provided a datum point for the strategic planning of physical conversion processes.

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Climate change, overpopulation and the decreasing availability of fossil fuels require the society to move towards sustainable and renewable resources. It can be anticipated that renewable energies will inevitably replace fossil fules and dominate the world's energy supply system in the long term. In order for these new energy sources to become completely reliable to meet with the growing energy demand, much research effort has been focused on energy storage technologies, especially those realted with electricity, such as supercapacitors. With regards to electrical energy storage devices, supercapacitors could fill the gap between batteries and conventional solid state and electrolytic capacitors. They store electrical energy through double layer charging, faradaic processes, or a combination of both. This thesis deals with the fabrication and study of prototype supercapacitors using conducting polymers and advanced carbons as the electrode materials. The work includes the synthesis of PPy-CNT and PANi-CNT nanocomposites, fundamental and electrochemical characterisations of conducting polymers and advanced carbons, electrode fabrication, and electrochemical performance of prototype supercapacitors. Additionally, this thesis aims to enhance the performance of prototype supercapacitors by improving the electrochemical properties of the existing electrode materials for supercapacitors, optimising the design of unit cells and stacks, and simplifying electrode fabrication.

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Calcium-Copper-Titanate (CCTO) is one of a class of non-ferroelectric, highly tilted Perovskite-structured oxides. Theoretical values of permittivity for these materials are low and fairly typical for non-ferroelectrics, yet these materials received considerable attention when reports of extremely high permittivity (in excess of 10,000) emerged, with one study on CCTO published in Science that attempted to assign the unusual behaviour to an as yet unknown exotic polarisation mechanism. This thesis proves that the high permittivity is actually extrinsic in origin and originates from a barrier layer capacitance effect; the measured values for intrinsic permittivity for CCTO and related ceramics was found to be low and comparable to theoretical values.

The work in this thesis focuses on the characterization, modeling and emulation of both the supercapacitor and the new supercapattery energy storage device. The characterization involves the selection of dynamic models and experimental methodologies to derive model parameters. The characterizing processes focus on predicting short-term device dynamics, energy retention (self-discharging) and losses and round-trip efficiency. A methodology involving a pulse current method is applied for the first time to identify a model parameter to give fast device dynamic characteristics and a new constant power cycling method is used for evaluating round-trip efficiency. Experimental results are shown for a number of supercapacitor and supercapattery devices and good results are obtained. The derived models from the characterization results are implemented into the emulator system and the emulator system is used to mimic the dynamic characteristics of a scaled-up 1kW supercapattery device. The thesis also addresses voltage equalizing circuits and reports a study that investigates efficiency, a cell voltage deviation and voltage equalizing time for different control methods.