Hermetically sealed lithium secondary battery

摘要

A hermetically sealed lithium secondary battery is provided which has an excellent battery performance and in which a current-interrupt mechanism operates accurately when overcharging occurs. This battery comprising an electrode assembly 80 that has a positive electrode 10. The positive electrode 10 has a positive electrode current collector 12, a positive electrode mixture layer 14 formed on the current collector, and a positive electrode assist layer 16 formed on the current collector and adjacent to the positive electrode mixture layer 14.

主权项

1. A hermetically sealed lithium secondary battery comprising
an electrode assembly that has a positive electrode and a negative electrode, a battery case that houses the electrode assembly and an electrolyte, and a current-interrupt mechanism that operates when the internal pressure of the battery case has risen, wherein the positive electrode comprising a positive electrode current collector and a positive electrode mixture layer formed on the positive electrode current collector and including a positive electrode active material, an electroconductive material, and a binder; the negative electrode comprising a negative electrode current collector and a negative electrode mixture layer formed on the negative electrode current collector and including a negative electrode active material and a binder; a positive electrode assist layer that includes an electroconductive material and a binder and that substantially does not contain a positive electrode active material is formed on the positive electrode current collector in at least a portion of an area adjacent to the positive electrode mixture layer; the positive electrode mixture layer is not formed on the area; and the electrolyte contains an overcharge inhibitor that generates a gas when a prescribed battery voltage is exceeded.