	US 12,355,103 B2
	Separator for lithium secondary battery and method for manufacturing the same
Kyung-Ryun Ka, Daejeon (KR); Jin-Young Shin, Daejeon (KR); Sang-Joon Lee, Daejeon (KR); and Je-An Lee, Daejeon (KR)
Assigned to LG ENERGY SOLUTION, LTD., Seoul (KR)
Appl. No. 17/801,423
Filed by LG ENERGY SOLUTION, LTD., Seoul (KR)
PCT Filed Feb. 26, 2021, PCT No. PCT/KR2021/002513 § 371(c)(1), (2) Date Aug. 22, 2022, PCT Pub. No. WO2021/172958, PCT Pub. Date Sep. 2, 2021.
Claims priority of application No. 10-2020-0024456 (KR), filed on Feb. 27, 2020.
Prior Publication US 2023/0086309 A1, Mar. 23, 2023
Int. Cl. H01M 50/449 (2021.01); H01M 10/0525 (2010.01); H01M 50/403 (2021.01); H01M 50/414 (2021.01); H01M 50/42 (2021.01); H01M 50/426 (2021.01); H01M 50/434 (2021.01); H01M 50/446 (2021.01); H01M 50/491 (2021.01)

CPC H01M 50/449 (2021.01) [H01M 10/0525 (2013.01); H01M 50/403 (2021.01); H01M 50/414 (2021.01); H01M 50/42 (2021.01); H01M 50/426 (2021.01); H01M 50/434 (2021.01); H01M 50/446 (2021.01); H01M 50/491 (2021.01)]

14 Claims

1. A separator for a lithium secondary battery, comprising:

a porous polymer substrate having a plurality of pores; and

a porous coating layer formed on at least one surface of the porous polymer substrate, wherein the porous coating layer comprises a plurality of inorganic particles and adhesive polymer particles positioned on a whole or a part of a surface of the inorganic particles to connect and fix the inorganic particles with one another,

wherein the inorganic particles comprise small-particle diameter inorganic particles having a diameter (D₅₀) of 10 nm to 100 nm and large-particle diameter inorganic particles having a diameter (D₅₀) of 600 nm or more, and an amount of the small-particle diameter inorganic particles is 30 parts by weight or more based on 100 parts by weight of a total amount of the inorganic particles,

wherein the adhesive polymer particles have a diameter (D₅₀) of 200 nm or less, and

wherein the porous coating layer has a porosity of 40% to 50%.