A lithium secondary battery comprising positive and negative electrodes both capable of occluding and releasing lithium ions, and a lithium ion conductive material which contains a compound of formula (1) exhibits improved characteristics including charge/discharge efficiency, low-temperature properties and cycle performance when (a) only one substituent group of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 in formula (1) is alkyl, (b) the negative electrode-constituting material partially contains a carboxyl or hydroxyl group-bearing compound, and the lithium ion conductive material contains propylene carbonate, or (c) a positive electrode active material is a lithium-containing transition metal compound, a negative electrode active material is a carbonaceous material, and the lithium ion conductive material contains as a non-aqueous electrolysis solution a solvent mixture of propylene carbonate and ethylene carbonate in combination with a chain-like carbonate as a low-viscosity solvent ##STR00001##