Patent ID: 8389156
Filing Date: 2013-03-05
Classification: H01M,Y02E

Abstract:
1. A negative electrode for a non-aqueous electrolyte secondary battery, comprising: a current collector having depressions and protrusions on the surface of one face or both faces in a thickness direction thereof; and a negative electrode active material layer that includes columns containing a negative electrode active material that absorbs and releases lithium ions, wherein the columns are grown outwardly from the surface of the current collector having the depressions and the protrusions, the columns are inclined at an angle relative to the direction perpendicular to the surface of the current collector, said columns are configured such that the inclination angle of the columns relative to the direction perpendicular to the surface of the current collector changes reversibly depending on absorption and release of lithium ions by the negative electrode active material, each of the columns includes an upper columnar part and a lower columnar part, the lower columnar part expands and contracts due to absorption and release of lithium more than the upper columnar part, the upper columnar part is a part of the column located on an obtuse angle side in a cross-section of the column in the thickness direction of the current collector, an obtuse angle being formed between a center line of the column in the grow direction thereof and a center line of the current collector in a longitudinal direction thereof, and the lower columnar part is a part of the column located on an acute angle side in the cross-section of the column in the thickness direction of the current collector, an acute angle being formed between the center line of the column in the grow direction thereof and the center line of the current collector in the longitudinal direction thereof.