LITHIUM SECONDARY BATTERY

An object is to provide a lithium secondary battery in which an uneven distribution of an electrolyte inside the battery is eliminated so as to suppress a decrease in performance.It is characterized in that in a lithium secondary battery including a cathode, an anode, and a semi-solid electrolyte layer, the semi-solid electrolyte layer contains an ionic liquid, an electrolytic solvent selected from glymes represented by the formula 1: RO-(CHCHO)-R (Formula 1) (wherein R is an alkyl group having 1 to 4 carbon atoms, and n is an integer of 1 to 4), and a lithium salt, inactive particles that do not occlude or emit lithium ions are included at least in the semi-solid electrolyte layer among the cathode, the anode, and the semi-solid electrolyte layer, the cathode, the anode, and the semi-solid electrolyte layer are porous structures having pores, in the semi-solid electrolyte layer, the electrolytic solvent and the lithium salt are retained in the pores, the pores have an average pore diameter of 0.01 µm or more and 0.6 µm or less, and the inactive particles in the semi-solid electrolyte layer have a volume fraction of 33% or more and 80% or less.