Aluminium corrosion in a room temperature molten salt is studied to validate the use of a new kind of electrolyte in a lithium battery. Two solvents have been compared, the room temperature molten salt ethyl-methyl-imidazolium bis(trifluoromethane-sulfonyl)imide (EMI-TFSI), and the liquid organic solvent EC/DMC containing the lithium salt LiTFSI. After confirmation of high aluminium corrosion in the liquid solvent, the results does not show the occurrence of corrosion in the room temperature molten salt. (C) 2004 Elsevier B.V. All rights reserved.