US 11,658,301 B2
Lithium secondary battery and method of preparing the same
Won Kyung Shin, Daejeon (KR); Kyoung Ho Ahn, Daejeon (KR); Chul Haeng Lee, Daejeon (KR); and Jae Won Lee, Daejeon (KR)
Assigned to LG ENERGY SOLUTION, LTD., Seoul (KR)
Appl. No. 16/770,931
Filed by LG CHEM, LTD., Seoul (KR)
PCT Filed Apr. 1, 2019, PCT No. PCT/KR2019/003818
§ 371(c)(1), (2) Date Jun. 8, 2020,
PCT Pub. No. WO2019/198961, PCT Pub. Date Oct. 17, 2019.
Claims priority of application No. 10-2018-0041812 (KR), filed on Apr. 10, 2018.
Prior Publication US 2021/0167392 A1, Jun. 3, 2021
Int. Cl. H01M 50/449 (2021.01); H01M 4/62 (2006.01); H01M 10/0525 (2010.01); H01M 10/058 (2010.01); H01M 50/443 (2021.01); H01M 4/02 (2006.01)
CPC H01M 4/623 (2013.01) [H01M 10/058 (2013.01); H01M 10/0525 (2013.01); H01M 50/443 (2021.01); H01M 50/449 (2021.01); H01M 2004/027 (2013.01); H01M 2004/028 (2013.01); H01M 2300/0028 (2013.01); H01M 2300/0085 (2013.01)] 17 Claims
 
1. A lithium secondary battery comprising:
a positive electrode;
a negative electrode;
a separator comprising a coating layer that includes an organic binder and inorganic particles; and
a gel polymer electrolyte formed by polymerization of an oligomer,
wherein the organic binder comprises a main chain composed of unit represented by Formula X-1 or Formula X-2 and wherein an epoxy group, a functional group capable of undergoing a ring-opening reaction with an epoxy group, or a combination thereof is substituted into the main chain, and
the organic binder and the gel polymer electrolyte are bonded by an epoxy ring-opening reaction:

OG Complex Work Unit Chemistry
wherein in Formula X-1, ml is an integer of 1 to 10,000,

OG Complex Work Unit Chemistry
in Formula X-2, m2 and m3 are each independently an integer of 1 to 10,000 and
the oligomer comprises at least one compound selected from the group consisting of compounds represented by Formula 2 and Formula 3:

OG Complex Work Unit Chemistry
wherein, in Formula 2, n1 is an integer of 2 to 10,000,

OG Complex Work Unit Chemistry
wherein, in Formula 3,
R6 to R11 are each independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms,
R12 to R16 are each independently at least one selected from the group consisting of hydrogen (H), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, —NR17R18, and —R19NR20R21, wherein R19 is a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms, and R17, R18, R20, and R21 are each independently hydrogen (H), a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms, and —R22NH2, wherein R22 is a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms, and
n2 is an integer of 1 to 10,000.