公开(公告)号：US09825281B2

公开(公告)日：2017-11-21

申请号：US13629001

申请日：2012-09-27

Applicant: GS YUASA INTERNATIONAL LTD.

Inventor： Daisuke Endo ,  Miki Yasutomi ,  Yoshihiro Katayama ,  Toshiyuki Nukuda

IPC: H01M4/04 ,  H01M4/505 ,  H01M4/525 ,  H01M10/052 ,  C01G45/12 ,  C01G51/00 ,  C01G53/00 ,  H02J7/00 ,  H01M10/44

CPC classification number: H01M4/0445 ,  C01G45/1228 ,  C01G51/42 ,  C01G51/50 ,  C01G53/50 ,  C01P2002/50 ,  C01P2002/72 ,  C01P2002/74 ,  C01P2002/77 ,  C01P2004/82 ,  C01P2006/40 ,  H01M4/505 ,  H01M4/525 ,  H01M10/052 ,  H01M10/446 ,  H02J7/00 ,  Y10T29/49108

Abstract: A lithium secondary battery is produced by employing a charging method where a positive electrode upon charging has a maximum achieved potential of 4.3 V (vs. Li/Li+) or lower. The lithium secondary battery contains an active material including a solid solution of a lithium transition metal composite oxide having an α-NaFeO2-type crystal structure. The solid solution has a diffraction peak observed near 20 to 30° in X-ray diffractometry using CuKα radiation for a monoclinic Li[Li1/3Mn2/3]O2-type before charge-discharge. The lithium secondary battery is charged to reach at least a region with substantially flat fluctuation of potential appearing in a positive electrode potential region exceeding 4.3 V (vs. Li/Li+) and 4.8 V (vs. Li/Li+) or lower. A dischargeable electric quantity in a potential region of 4.3 V (vs. Li/Li+) or lower is 177 mAh/g or higher.