A series of new hydrophobic ionic liquids based on 1-alkyl-quinuclidinium cations, quoted as C _n Quin⁺ where n is the number of carbon atoms in the alkyl chain, and on the fluorinated anion bis(trifluoromethanesulfonyl)imide (TFSI⁻) were synthesized, characterized by NMR (¹H, ¹³C), and their elemental analysis determined. Among the five compounds synthesized, only one: C₆Quin(TFSI) is liquid at ambient temperature and the others with the exception of C₁Quin(TFSI), exhibit melting points below 100 °C and can be considered as ionic liquids. With the aim of using them as electrolytes in electrochemical devices, some of their physicochemical properties such as density, dynamic viscosity and conductivity were explored. The behaviour of C₆Quin(TFSI) at a graphite electrode was investigated in the presence of added LiTFSI, by means of cyclic voltammetry for possible use as electrolyte in Li-ion batteries. Results show that the large quinuclidinium cations intercalate in the graphite layers and do not permit the reversible insertion of lithium ions.