公开(公告)号：US09755237B2

公开(公告)日：2017-09-05

申请号：US14893027

申请日：2014-05-22

Applicant: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.

Inventor： Akira Kano ,  Nobuhiko Hojo ,  Masahisa Fujimoto

IPC: H01M4/587 ,  H01M4/133 ,  C01B31/00 ,  C01B31/02 ,  H01M10/054 ,  H01M4/02

CPC classification number: H01M4/587 ,  C01B32/00 ,  C01B32/05 ,  C01B32/30 ,  C01B32/318 ,  H01M4/133 ,  H01M10/054 ,  H01M2004/021 ,  H01M2004/027

Abstract: A negative-electrode active material for a sodium-ion secondary battery contains a porous carbon material which has a plurality of open pores that extend through to the surface, a plurality of closed pores that do not extend through to the surface, and a solid portion made of carbon material. The distance between (002) planes of carbon in at least a part of the solid portion is 0.36 nm or more. The plurality of closed pores account for a volume ratio of not less than 30% and not more than 90% with respect to a total volume of the plurality of open pores, the plurality of closed pores, and the solid portion.