US 12,230,837 B2
Separator having coating layer with ternary acrylic copolymer and inorganic particles with different particle diameters, and lithium secondary battery comprising same
Jungyoon Lee, Yongin-si (KR); Gain Kim, Yongin-si (KR); Yangseob Kim, Yongin-si (KR); Yongkyoung Kim, Yongin-si (KR); and Yeonjoo Choi, Yongin-si (KR)
Assigned to Samsung SDI Co., Ltd., Yongin-si (KR)
Appl. No. 17/296,501
Filed by Samsung SDI Co., Ltd., Yongin-si (KR)
PCT Filed Aug. 9, 2019, PCT No. PCT/KR2019/010128
§ 371(c)(1), (2) Date May 24, 2021,
PCT Pub. No. WO2020/130270, PCT Pub. Date Jun. 25, 2020.
Claims priority of application No. 10-2018-0167507 (KR), filed on Dec. 21, 2018.
Prior Publication US 2022/0037741 A1, Feb. 3, 2022
Int. Cl. H01M 50/451 (2021.01); C08F 220/56 (2006.01); C08K 3/22 (2006.01); H01M 10/0525 (2010.01); H01M 50/417 (2021.01); H01M 50/42 (2021.01); H01M 50/423 (2021.01); H01M 50/434 (2021.01); H01M 50/443 (2021.01); H01M 50/446 (2021.01); H01M 50/489 (2021.01)
CPC H01M 50/451 (2021.01) [C08F 220/56 (2013.01); C08K 3/22 (2013.01); H01M 10/0525 (2013.01); H01M 50/42 (2021.01); H01M 50/423 (2021.01); H01M 50/434 (2021.01); H01M 50/443 (2021.01); H01M 50/446 (2021.01); H01M 50/489 (2021.01); C08F 2800/10 (2013.01); C08K 2003/2227 (2013.01); C08K 2201/005 (2013.01); C08K 2201/011 (2013.01); H01M 50/417 (2021.01)] 14 Claims
OG exemplary drawing
 
1. A separator for a lithium secondary battery, comprising
a porous substrate, and
a coating layer on at least one surface of the porous substrate,
wherein the coating layer comprises:
a binder including a (meth)acrylic copolymer;
first inorganic particles; and
second inorganic particles,
wherein the (meth)acrylic copolymer is a ternary copolymer consisting of a first structural unit, a second structural unit and a third structural unit:
the first structural unit being derived from (meth)acrylamide including an amide functional group (—NH2);
the second structural unit including at least one of a structural unit derived from (meth)acrylic acid or (meth)acrylate; and
the third structural unit being derived from (meth)acrylamidosulfonic acid or a salt thereof,
wherein the first inorganic particles have an average particle diameter of 400 to 600 nm, and
an average particle diameter of the second inorganic particles is smaller than the average particle diameter of the first inorganic particles, and
wherein the average particle diameter of the second inorganic particles is 50 to 200 nm.