US 11,843,125 B2
Porous composite separator for secondary battery, and lithium secondary battery comprising same
Hye Jin Kim, Daejeon (KR); Yun Bong Kim, Daejeon (KR); Suji Lee, Daejeon (KR); Won Sub Kwack, Daejeon (KR); and Kyu Young Cho, Daejeon (KR)
Assigned to SK Innovation Co., Ltd., Seoul (KR); and SK ie technology Co., Ltd., Seoul (KR)
Appl. No. 16/769,707
Filed by SK Innovation Co., Ltd., Seoul (KR); and SK IE Technology Co., Ltd., Seoul (KR)
PCT Filed Dec. 4, 2018, PCT No. PCT/KR2018/015228
§ 371(c)(1), (2) Date Jun. 4, 2020,
PCT Pub. No. WO2019/112283, PCT Pub. Date Jun. 13, 2019.
Claims priority of application No. 10-2017-0167299 (KR), filed on Dec. 7, 2017.
Prior Publication US 2020/0373538 A1, Nov. 26, 2020
Int. Cl. H01M 50/446 (2021.01); H01M 10/0525 (2010.01); H01M 50/409 (2021.01); H01M 50/40 (2021.01); H01M 50/451 (2021.01); H01M 50/491 (2021.01); H01M 50/417 (2021.01); H01M 50/42 (2021.01); H01M 50/457 (2021.01)
CPC H01M 50/446 (2021.01) [H01M 10/0525 (2013.01); H01M 50/40 (2021.01); H01M 50/409 (2021.01); H01M 50/417 (2021.01); H01M 50/42 (2021.01); H01M 50/451 (2021.01); H01M 50/457 (2021.01); H01M 50/491 (2021.01)] 15 Claims
OG exemplary drawing
 
1. A porous composite separator for a secondary battery comprising: a porous substrate and a coating layer formed on the porous substrate,
wherein the coating layer is formed by a plurality of inorganic particles which are connected and fixed by a composite binder including a particle type polymer binder and an interpenetrating polymer network (IPN) type binder having no melting point and having a thermal decomposition temperature of 300° C. or higher and having a crosslinking penetration degree of 20 or less,
wherein the particle type polymer binder has an average particle diameter of more than 100 nm and 10 μm or less, and
wherein the average particle diameter of the particle type polymer binder satisfies the following Equation 1:

OG Complex Work Unit Math
wherein
Rs is the average pore size of the porous substrate, and Rp is the average particle diameter of the particle type polymer binder.