US 11,855,303 B2
Cylindrical lithium ion secondary battery
Byoung Min Chun, Yongin-si (KR)
Assigned to Samsung SDI Co., Ltd., Yongin-si (KR)
Appl. No. 16/965,258
Filed by Samsung SDI Co., Ltd., Yongin-si (KR)
PCT Filed Jan. 2, 2019, PCT No. PCT/KR2019/000047
§ 371(c)(1), (2) Date Jul. 27, 2020,
PCT Pub. No. WO2019/151662, PCT Pub. Date Aug. 8, 2019.
Claims priority of application No. 10-2018-0012754 (KR), filed on Feb. 1, 2018.
Prior Publication US 2021/0074978 A1, Mar. 11, 2021
Int. Cl. H01M 50/342 (2021.01); H01M 50/107 (2021.01); H01M 10/0525 (2010.01); H01M 10/0587 (2010.01)
CPC H01M 50/3425 (2021.01) [H01M 10/0525 (2013.01); H01M 50/107 (2021.01); H01M 10/0587 (2013.01); H01M 2200/20 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A cylindrical lithium ion secondary battery comprising:
a cylindrical can;
an electrode assembly accommodated in the cylindrical can; and
a cap assembly for sealing the cylindrical can,
wherein the cylindrical can comprises a circular floor portion, a curved portion on the floor portion and curved from the floor portion towards the electrode assembly, and a safety vent formed on the curved portion,
wherein the curved portion includes a pair of curve portions curved from the floor portion toward the electrode assembly and a flat portion connecting the pair of curve portions, wherein the flat portion includes a substantially planar first surface and a substantially planar second surface opposite the substantially planar first surface,
wherein the curved portion is configured to receive material associated with a formation of the safety vent for maintaining a substantially planar surface of the floor portion, and the floor portion, the pair of curve portions, and the flat portion, have a same thickness.