Granted Patent B2

US 12,327,881 · App. 18/216,293 · Granted Jun 10, 2025

Inventors: Zhong Xu (Holden, MA); Steven A. Carlson (Cambridge, MA)

Assignees: LG Energy Solution, Ltd.; Sihl GmbH

H01M50/446H01G9/02H01G11/52H01M10/0525Y02E60/13Y10T428/249978

Abstract

Claims (27)

1. A method of coating a substrate for a battery separator comprising the steps of:

(a) providing a dispersion of hydrated aluminum oxide that is dispersible in aprotic solvents;

(b) providing an organic polymer solution comprising an organic polymer that is soluble in aprotic solvents;

(c) mixing the dispersion of step (a) and the solution of step (b) so as to make a mixture;

and

(d) forming a coating on a substrate by applying the mixture of step (c) onto the substrate.

2. The method of claim 1 , wherein the hydrated aluminum oxide that is dispersible in aprotic solvents has been made by treating a hydrated aluminum oxide with a sulfonic acid to provide hydrated aluminum oxide having dispersibility in aprotic solvents.

3. The method of claim 1 , wherein the substrate is a release substrate and the method further comprises the steps of: (e) drying the coating of the substrate so as to make a dry coating and (f) delaminating the dry coating from the release substrate.

4. The method of claim 1 , wherein the substrate is a porous separator material.

5. The method of claim 4 , wherein the porous separator material is a polyolefin separator material.

6. A method of making an electric current-producing cell comprising the steps of:

(a) providing an anode;

(b) providing a cathode; and

(c) interposing a microporous separator between the anode and the cathode to form an electric current-producing cell, wherein the microporous separator comprises a microporous layer comprising: a hydrated aluminum oxide that is dispersible in aprotic solvents and an organic polymer that is soluble in aprotic solvents.

7. The method of claim 6 , wherein the hydrated aluminum oxide that is dispersible in aprotic solvents has been made by treating a hydrated aluminum oxide with a sulfonic acid to provide hydrated aluminum oxide having dispersibility in aprotic solvents.

8. The method of claim 7 , wherein the sulfonic acid is an aryl sulfonic acid.

9. The method of claim 6 , further comprising the steps of:

(d) enclosing the electric current-producing cell in a casing;

(e) filling the casing with electrolyte; and optionally

(f) sealing the casing.

10. The method of claim 6 , wherein the microporous layer comprises a xerogel layer.

11. The method of claim 10 , wherein the microporous layer comprises a continuous xerogel layer with a porosity of at least 30%.

12. The method of claim 6 , wherein the organic polymer comprises a polyvinylidene fluoride polymer.

13. The method of claim 6 , wherein the organic polymer comprises a first fluorinated organic monomer and a second organic monomer.

14. The method of claim 6 , wherein the hydrated aluminum oxide comprises a hydrated aluminum oxide of the formula Al 2 O 3 ·xH 2 O, wherein x is in the range of 1.0 to 1.5.

15. The method of claim 6 , wherein the separator comprises 50% to 85% by weight of the hydrated aluminum oxide.

16. The method of claim 6 , wherein the microporous layer has an average pore diameter from 2 nm to 70 nm.

Continuity (6)

References Cited (240)