Patent ID: 9099755
Filing Date: 2015-08-04
Classification: H01M,Y02E,Y02P

Abstract:
1. A lithium secondary battery, comprising: an electrode group, including a first electrode, a second electrode, and a separator disposed between the first electrode and the second electrode; a first electrode tab connected to the first electrode; and a second electrode tab connected to the second electrode, wherein the first electrode tab includes a first portion connected to the first electrode and a second portion, and a width of the first portion is less than a width of the second portion, wherein the first electrode has a tab junction protruding from a side of the first electrode to be connected to the first portion, and the tab junction is an uncoated portion on which electrode active material is not coated, the tab junction having an active material border between a portion on which the electrode active material is formed and a portion on which the electrode active material is not formed, the width of the tab junction is equal to or larger than the width of the first portion, the width of the tab junction of the first electrode is less than a width of the second portion, and a ratio of the width of the first portion to the width of the second portion ranges from 0.35 to 0.6.