公开(公告)号：US20240145760A1

公开(公告)日：2024-05-02

申请号：US18398471

申请日：2023-12-28

Applicant: BYD COMPANY LIMITED

Inventor： Yi PAN ,  Yongjun MA ,  Zizhu GUO ,  Liangjun WANG ,  Huajun SUN

IPC: H01M10/052 ,  H01M4/02 ,  H01M4/04 ,  H01M4/38 ,  H01M10/0569 ,  H01M10/058 ,  H01M10/44 ,  H01M50/249

CPC classification number: H01M10/052 ,  H01M4/0416 ,  H01M4/0435 ,  H01M4/382 ,  H01M4/386 ,  H01M10/0569 ,  H01M10/058 ,  H01M10/44 ,  H01M50/249 ,  H01M2004/027 ,  H01M2220/20

Abstract: A lithium battery includes a positive electrode plate, a negative electrode plate, a separator located between the positive electrode plate and the negative electrode plate, and an electrolyte solution. The negative electrode material layer of the negative electrode plate includes a lithium-silicon composite negative electrode active material. The negative electrode material layer has a protective layer on the surface or the lithium-silicon composite negative electrode active material has a protective layer on the surface. The protective layer includes a polymer matrix and a lithium salt. When the lithium battery is fully charged, the lithium-silicon composite negative electrode active material includes elemental lithium and a lithium-silicon alloy Li4.4Si, and the elemental lithium accounts for 15%-95% by mole of the lithium-silicon composite negative electrode active material.