Non-conventional electrolytes for electrochemical applications

Several non-conventional electrolytes, molten salts, liquefied gas and supe rcritical fluids, are reviewed to show their usefulness and their possibili ties in electrochemical applications. Special attention is paid to chemical and material production, material tailoring and energy conversion. In this work, molten salts are divided into high (T > 473 K) and room (273 K less than or equal to T less than or equal to 473 K) temperature salts. Characte rs and properties of representative molten salts are described for the corr esponding temperature range. Some selected topics, mainly using molten hali des, e.g. production of SiH4 gas, formation of metal nitrides, thermally re generative fuel cells and thermogalvanic cells, are presented in the high t emperature section. In the room temperature part, applications based on chl oroaluminate melts such as AlCl3-EMIC melts are described, including electr odeposition of Al and Al alloys, Li batteries and capacitors. Finally, liqu efied gas systems, such as NH3 and HCl, and supercritical fluids like super critical water and CO2 are briefly mentioned as examples of new class non-c onventional electrolytes. (C) 2000 Elsevier Science Ltd. All rights reserve d.