Electrode for Lithium Ion Secondary Battery, Method of Manufacturing the Same and Lithium Ion Secondary Battery Comprising the Same

Patent metadata

Field	Value
Publication number	US-2025309269-A1
Application number	US-202418863736-A
Country	US
Kind code	A1
Filing date	Apr 1, 2024
Priority date	Apr 24, 2023
Publication date	Oct 2, 2025
Grant date	—

Abstract

An electrode for a lithium ion secondary battery includes; an electrode active material layer, an electrode current collector layer, and a porous layer laminated on the electrode current collector layer. The porous layer includes a polymer binder including a copolymer containing a hard segment of the following Chemical Formula 1 and a soft segment of the following Chemical Formula 2 and inorganic fine particles dispersed in the polymer binder:

Also provided is a method of manufacturing the same and a lithium ion secondary battery comprising the same. The electrode for the lithium ion secondary battery has a dense bond between a porous layer and an electrode active material layer and also imparts high flexibility to the porous layer which results in exhibiting excellent durability during charge and discharge.

First claim

1 . An electrode for a lithium ion secondary battery, comprising:
an electrode active material layer; an electrode current collector layer; and
a porous layer laminated on the electrode current collector layer,
wherein the porous layer comprises a polymer binder including a copolymer containing a hard segment of the following Chemical Formula 1 and a soft segment of the following Chemical Formula 2 and inorganic fine particles dispersed in the polymer binder:

wherein in Chemical Formula 1:
R1 and R3 are each independently or

A 1 to A 3 are each independently hydrogen or an alkyl group having 1 to 3 carbon atoms, and L 1 is a chemical bond or a methylene group, and
R 2 is an alkylene group having 1 to 5 carbon atoms;

wherein in Chemical Formula 2, R 4 is an alkylene group having 3 to 6 carbon atoms.

2 . The electrode according to claim 1 , wherein the R 1 and R 3 are each independently

3 . The electrode according to claim 1 , wherein the copolymer includes the hard segment and the soft segment at a molar ratio ranging from 80:20 to 95:5.

4 . The electrode f according to claim 1 , wherein the copolymer has a weight average molecular weight (Mw) of ranging from 100,000 g/mol to 1,000,000 g/mol.

5 . The electrode according to claim 1 , wherein the polymer binder further comprises one or more binder compounds, selected from the group consisting of polyetherimide, polyvinylidene fluoride, poly(vinylidene fluoride-co-trichloroethylene), poly(vinylidene fluoride-co-chlorotrifluoroethylene), poly(vinylidenefluoride-co-trifluoroethylene), poly(vinylidenefluoride-co-tetrafluoroethylene), poly(vinylidenefluoride-co-hexafluoropropylene), butylacrylate, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, ethylene vinyl acetate copolymer, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethylated polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, ethylene-propylene-diene terpolymer, sulfonated ethylene-propylene-diene terpolymer, styrene butadiene rubber, fluororubber, and polyimide.

6 . The electrode according to claim 5 , wherein the binder compounds are included in an amount of 10 wt. % or more based on a total weight of the polymer binder including the copolymer containing the hard segment of Chemical Formula 1 and the soft segment of Chemical Formula 2.

7 . The electrode according to claim 1 , wherein the inorganic fine particles are one or more selected from the group consisting of SrTiO 3 , SnO 2 , CeO 2 , MgO, NiO, CaO, ZnO, ZrO 2 , Y 2 O 3 , Al 2 O 3 , AlO(OH), Al(OH) 3 , TiO 2 , SiC, BaTiO 3 , Pb(Zr,Ti)O 3 , Pb 1-x La x Zr 1-y Ti y O 3 , Pb(Mg 1/3 Nb 2/3 )O 3 —PbTiO 3 , HfO 2 , Li 3 PO 4 , Li x Ti y (PO 4 ) 3 (0<x<2, 0<y<3), Li x Al y Ti z (PO 4 ) 3 (0<x<2, 0<y<1, 0<z<3), (LiAlTiP) x O y (0<x<4, 0<y<13), Li x La y TiO 3 (0<x<2, 0<y<3), Li x Ge y P z S w (0<x<4, 0<y<1, 0<z<1, 0<w<5), Li x N y (0<x<4, 0<y<2), Li x Si y S z (0<x<3, 0<y<2, 0<z<4), and Li x P y S z (0<x<3, 0<y<3, 0<z<7).

8 . The electrode according to claim 1 , wherein the inorganic fine particles have a particle size ranging from 0.001 μm to 10 μm.

9 . The electrode according to claim 1 , wherein the porous layer includes a range of 0.5 to 45 wt. % of the polymer binder and a range of 55 to 99.5 wt. % of the inorganic fine particles.

10 . A method of manufacturing the electrode for the lithium ion secondary battery according to claim 1 , comprising:
forming an electrode active material layer by applying an electrode material composition containing an electrode active material onto an electrode current collector layer; preparing an inorganic fine particle dispersion in which inorganic fine particles and a dispersant are dispersed in a solvent. preparing a binder solution in which a polymer binder including a copolymer containing a hard segment of the following Chemical Formula 1 and a soft segment of the following Chemical Formula 2 is dissolved in a solvent; preparing a slurry for forming a porous layer by mixing the binder solution with the inorganic fine particle dispersion; and forming a porous layer by applying the slurry for forming a porous layer onto the electrode active material layer:

wherein in Chemical Formula 1:
R 1 and R 3 are each independently

A 1 to A 3 are each independently hydrogen or an alkyl group having 1 to 3 carbon atoms, and L 1 is a chemical bond or a methylene group, and;
R 2 is an alkylene group having 1 to 5 carbon atoms;
R 4 —O n   [Chemical Formula 2]

wherein in Chemical Formula 2, R 4 is an alkylene group having 3 to 6 carbon atoms.

11 . The manufacturing method according to claim 10 , wherein the slurry for forming a porous layer has a range of 55 wt. % to 99.5 wt. % of a solid content including the inorganic fine particles.

12 . A slurry for forming a porous layer of an electrode for a lithium ion secondary battery, comprising:
a polymer binder including a copolymer containing a hard segment of the following Chemical Formula 1 and a soft segment of the following Chemical Formula 2 and inorganic fine particles dispersed in the polymer binder:

wherein in Chemical Formula 1:
R 1 and R 3 are each independently

A 1 to A 3 are each independently hydrogen or an alkyl group having 1 to 3 carbon atoms, and L 1 is a chemical bond or a methylene group, and;
R 2 is an alkylene group having 1 to 5 carbon atoms;

wherein in Chemical Formula 2,
R 4 is an alkylene group having 3 to 6 carbon atoms.

13 . The slurry according to claim 12 , wherein the copolymer includes the hard segment and the soft segment at a molar ratio ranging from 80:20 to 95:5.

14 . The slurry according to claim 12 , wherein the polymer binder and the inorganic fine particles are included in a ratio ranging from 0.5 to 45 wt. %:55 to 99.5 wt. %.

15 . A lithium ion secondary battery comprising the electrode for the lithium ion secondary battery according to claim 1 .

Assignees

• Lg Chemical Ltd

Inventors

• Yu Ingyoung
• Lee Kyoungsoo
• Kim Su Jun
• Jin Sun Mi

Classifications

• H01M10/0525 Primary

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/366

  as layered products · CPC title

• H01M4/1391

  of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/0404

  by coating on electrode collectors · CPC title