	US 12,394,863 B2
	Composite separator for lithium secondary battery and manufacturing the same
Chang Sup Lim, Seoul (KR); Kyoung Ran Im, Seoul (KR); and Soon Yong Jeong, Gwangmyeong-si (KR)
Assigned to G-MATERIALS CO., LTD., Gwangmyeong-si (KR)
Appl. No. 17/630,678
Filed by G-Materials Co., Ltd., Gwangmyeong-si (KR)
PCT Filed Aug. 24, 2020, PCT No. PCT/KR2020/011233 § 371(c)(1), (2) Date Jan. 27, 2022, PCT Pub. No. WO2021/034159, PCT Pub. Date Feb. 25, 2021.
Claims priority of application No. 10-2019-0102872 (KR), filed on Aug. 22, 2019.
Prior Publication US 2022/0320682 A1, Oct. 6, 2022
Int. Cl. H01M 50/446 (2021.01); H01M 10/42 (2006.01); H01M 50/403 (2021.01); H01M 50/414 (2021.01); H01M 50/431 (2021.01); H01M 50/451 (2021.01); H01M 10/0525 (2010.01); H01M 50/423 (2021.01); H01M 50/434 (2021.01); H01M 50/46 (2021.01)

CPC H01M 50/446 (2021.01) [H01M 10/4235 (2013.01); H01M 50/403 (2021.01); H01M 50/414 (2021.01); H01M 50/431 (2021.01); H01M 50/451 (2021.01); H01M 10/0525 (2013.01); H01M 50/423 (2021.01); H01M 50/434 (2021.01); H01M 50/461 (2021.01); Y02E 60/10 (2013.01)]

10 Claims

1. A composite separator for a lithium secondary battery comprising of;

(a) a porous polymer substrate,

(b) a heat-resistant coating layer of an inorganic material formed on the surface of the substrate,

(d) a surfactant,

wherein the binder is:

i) a composite binder which is a mixture of an organic-inorganic composite sol and either a first organic polymer or a modified organic polymer; or

ii) the modified organic polymer of (i), and

wherein the modified organic polymer comprises a hybrid sol obtained by reacting a second organic polymer with a carboxylic acid, and reinforced by further reaction with a nano-sized inorganic material, the carboxylic acid being one or more selected from the group consisting of maleic acid, oxalic acid, malic acid, succinic acid, and citric acid, and the nano-sized inorganic material being silica or boehmite.