Conventional experimental methods for testing the performance of super-capacitors include the measurement of capacitance through charge and discharge, measurement of equivalent series resistance (ESR) and measurement of self-discharge and the equivalent circuit model (ECM) by electrochemical impedance spectroscopy (EIS). However, the methods are not suitable for the mass production line of supercapacitors since they require a long time for the test and several kinds of different instrument. EIS is an attractive method to evaluate the performance of supercapacitors except that it takes a long time for a single test. In this paper a fast EIS instrument suitable for quality assurance for the mass production of supercapacitors is proposed. In order to reduce the time for the test, a multi-sine sweeping method is used for the EIS test and the results are analyzed by extracting the parameters of the ECM to evaluate the performance of the supercapacitors. The proposed instrument is developed to have multi-channel to further decrease the time for the test with a supercapacitor. It is also presented as to how the extracted parameter values of the ECM can be used to evaluate the performance of the supercapacitor.

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This work put forward the use of Lithium ion batteries as an energy storage medium with the existing uninterrupted power supplies, design for lead acid batteries by introducing an interface which takes care of different necessary parameters of Lithium Ion batteries is proposed. Li-ion battery has different voltage level per cell and demands more sophisticated control and safety measures as compare to Lead Acid battery. The interface will take its input from the UPS and will accordingly adjust its output for the Li-ion battery. The interface consists of a converter and a battery management system (BMS) for safe charging and discharging of Li-ion battery. A Li-ion battery pack topology is also proposed in the work, which ensures maximum energy extraction from the battery pack being used in UPS without compromising the life of battery pack and other constraints.