LITHIUM SECONDARY BATTERY AND PROCESS FOR PRODUCING SAME

摘要

Disclosed is a lithium secondary battery characterized in that a positive electrode active material comprises a lithium composite oxide containing at least lithium and nickel and/or cobalt as the main constituent elements, a positive electrode active material layer has a porosity of 30 to 40% inclusive, and a negative electrode active material layer has a porosity of 30 to 45% inclusive. In the lithium secondary battery, the void volume ratio (Sa/Sb) of the void volume (Sa) per unit area in the positive electrode active material layer to the void volume (Sb) per unit area in the negative electrode active material layer fulfils the requirement represented by the following formula: 0.9 = (Sa/Sb) = 1.4.