NEGATIVE-POLE MATERIAL MANUFACTURING METHOD FOR LITHIUM ION SECONDARY BATTERY AND NEGATIVE-POLE MATERIAL FOR LITHIUM ION SECONDARY BATTERY

摘要

The purpose of the present invention is to provide technology to further improve the high-charge capacity and the charging cycle characteristics of a lithium ion secondary battery. In order to achieve this purpose, a negative-pole material manufacturing method for a lithium ion secondary battery provided with a negative-pole mixture layer, which includes a negative-pole active material, on the surface of a negative-pole collector is applied, said method being characterized in that one or more materials selected from a granular material of a lithium alloy and a carbon material capable of absorbing and releasing lithium are used as the negative-pole active material, an electrolytic copper foil having a surface roughness (Ra) in the range of [0.053 × D50(c)] µm to [0.210 × D50(c)] µm is selectively used as the negative-pole collector when the surface roughness (Ra) is in the range of 0.20 µm 50(c)) of the negative-pole active material is set as a reference, a silane coupling agent processing layer is provided on the surface of the electrolytic copper foil, and the negative-pole mixture layer is formed by the negative-pole active material on the surface of the silane coupling agent processing layer to produce a negative-pole material.