公开(公告)号：US20240145687A1

公开(公告)日：2024-05-02

申请号：US18549274

申请日：2022-03-01

Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.

Inventor： Jo SAITO ,  Yohei MOMMA ,  Tatsuyoshi TAKAHASHI ,  Nao KUROSAWA ,  Kunihiko SUZUKI

IPC: H01M4/36 ,  H01M4/525 ,  H01M4/583 ,  H01M4/88 ,  H01M10/0525 ,  H01M10/0562

CPC classification number: H01M4/366 ,  H01M4/525 ,  H01M4/583 ,  H01M4/8882 ,  H01M10/0525 ,  H01M10/0562 ,  H01M2004/028

Abstract: A novel positive electrode active material, a novel positive electrode, and a novel lithium-ion secondary battery are to be provided. The lithium-ion secondary battery includes a positive electrode, a negative electrode, and an electrolyte. The positive electrode includes a positive electrode active material that includes a composite oxide containing lithium and cobalt. The positive electrode active material includes barium, magnesium, and aluminum in a surface portion. When being analyzed, the surface portion preferably includes a region where a first point of the highest barium concentration and a second point of the highest magnesium concentration exist closer to the surface than a third point of the highest aluminum concentration does.