Innovative methods of ball milling to grind activated carbon as an electrode material for enhancing the performance of ultracapacitor

摘要

It is estimated that the world will need to double its energy supply by 2050. So there is heightened need for improved electrical energy storage system, when the load on utility is low or moderate. The parameters of electrode material and electrolyte decides rating and performance of energy storing device. The performance of ultracapacitor has been investigated against variation in processing of the electrode material in this paper. To store bulk amount of electrical energy, it is very essential to develop energy storing devices of large capacity and large rating. The present energy storage devices and their conventional techniques of manufacturing it, are not useful to store bulk amount of electrical energy. The various types of activated carbons are available in the market. The energy storage device's performance is enhanced by utilizing different properties of activated carbon. The most of time, raw electrode materials do not have a grain size suited to make electrode from it, so, it is required to crush raw electrode material into fine powder. The capacitance of ultra capacitor depends on type of activated carbon, particle size, specific surface area and quantity/weight of activated carbon to be deposited on electrode surface and type of ball milling method adopted to crush electrode material. In present paper, three innovative ball milling units/machines are developed to crush electrode material into fine powder. The ultra capacitor are manufactured from this crushed electrode material and charging discharging test are performed to study the performance of ultra capacitor. The comparison between ultra capacitors is carried out to decide upon the best ball milling machine. It is observed that the performance of ultra capacitor depends on type of ball milling machine used to crush electrode material, speed of Ball Milling Machine, number of balls used, weight of balls, Ball milling time. The optimum values of these parameters are obtained to get the best overall performance of ultra capacitor.