Mesoporous Electrodes and Polymer supported Electrolytes for Efficiency of Electrochemical Energy Storage Devices

Kurzfassung

Previous studies displayed that the supercapacitor electrodes possessing high surface area and rich surface chemistry contribute to energy densities and charge rapidly. New mesoporous films which are a combination of graphene, CNT and carbon complexes preferably in core-shell architectures introduce superior capacitive charge-storage properties. Moreover, the electrolytes also play an important role for the increase of the potential window but must be compatible with the electrode materials as well as sustaining environmental retention and being durable under exceptional conditions such as these at space. Low-Orbit satellites require energy harvesting systems and the rapid charging, peak power storage devices for their long-term self-sufficient decentral operation. This work describes the fabrication and performance of the cells made of mesoporous carbon-based electrodes which are either embedded as composites or nano-structured and polymeric solid electrolytes containing integrated salts and ionic liquids. The electrode layers are deposited by doctor-blade technique or by vacuum deposition techniques and combined with polymer based electrolytes in pouch cells. For comparison of the specific and areal capacitance values, discharge capacitance retention and charge-discharge performances, the pouch cells consisted of carbon black electrodes and ionic liquid and LiClO4 based polymer electrolytes are manufactured and tested. The electrochemical performances, energy and power densities are calculated and compared. The cyclic charge and discharge behavior are considered in terms of discharge capacitance fading. The role of specific electrolyte and the effect of mesoporous electrode materials and conducting polymers are determined and the beneficial factors are demonstrated by means of Nyquist plots.