LITHIUM ION SECONDARY CELL

摘要

A lithium ion secondary cell in which abnormal overheat due to short circuit between the current collecting section of one electrode and the electrode mix of the other is prevented. The lithium ion secondary cell comprises a positive electrode which has a positive electrode core member having a positive electrode current collecting section and a mix supporting section and a positive electrode mix layer supported by the mix supporting section, a negative electrode which has a negative electrode core member having a negative electrode current collecting section and a mix supporting section and a negative electrode mix layer supported by the mix supporting section, a separator interposed between the positive and negative electrodes, a porous electron insulating layer interposed between the positive and negative electrodes and containing an inorganic oxide filler and a binder, and a nonaqueous electrolyte. The porous electron insulating layer is supported by a region including the surfaces of the positive current collecting section and the positive electrode mix layer and/or a region including the surfaces of the negative current collecting section and the negative electrode mix layer, and the positive and negative electrodes are wound with the separator and porous electron insulating layer interposed therebetween.