LITHIUM ION SECONDARY BATTERY AND PRODUCTION METHOD THEREFOR

摘要

Provided are a lithium ion secondary battery which is superior in safety and enables the realization of high energy density and high power density at a low cost without using a polymer separator such as a porous polyolefin separator, and a production method therefor. A ceramic separator layer (11) which comprises a composite material including insulating inorganic microparticles and an organic material and which has lithium ion permeability is disposed on the surface of a positive electrode (1) and/or a negative electrode (2), and a lithium ion permeable gel-containing layer (12) which includes a gel having electron insulating properties and lithium ion permeability is disposed on the surface of the ceramic separator layer (11). The gel included in the lithium ion permeable gel-containing layer is a gel having a chemical crosslink structure. The ceramic separator layer is disposed on the positive electrode and/or the negative electrode, and the lithium ion permeable gel-containing layer is formed thereupon so as to prevent the occurrence of defects such as flaking in the ceramic separator layer.