Highly permeable ceramic coated separators and related components, batteries, and methods

Patent metadata

Field	Value
Publication number	US-2026074370-A1
Application number	US-202519319345-A
Country	US
Kind code	A1
Filing date	Sep 4, 2025
Priority date	Sep 6, 2024
Publication date	Mar 12, 2026
Grant date	—

Abstract

In some embodiments, a separator includes a polymer membrane, and a separator coating disposed on the polymer membrane. The separator coating includes (1) ceramic particles including a mixture of higher-aspect ratio ceramic particles (HARCPs) and lower-aspect ratio ceramic particles (LARCPs) and (2) a binder. The separator coating may have a thickness of about 0.5 μm to about 5.0 μm and a mass fraction of the binder in the separator coating may be 20 wt. % or less. The ceramic particles may include Al2O3, AlO(OH), and/or Al(OH)3. The HARCPs may be characterized by an HARCP aspect ratio of more than about 3 and the LARCPs may be characterized by an LARCP aspect ratio of about 1 to about 3. Integrated electrode-separator components, lithium-ion batteries, and related methods are also disclosed.

First claim

1 . A separator, comprising:
a polymer membrane; and a separator coating disposed on the polymer membrane comprising (1) ceramic particles comprising a mixture of higher-aspect ratio ceramic particles (HARCPs) and lower-aspect ratio ceramic particles (LARCPs) and (2) a binder, the separator coating having a thickness of about 0.5 μm to about 5.0 μm, a mass fraction of the binder in the separator coating being about 20 wt. % or less, wherein: the ceramic particles comprise Al 2 O 3 , AlO(OH), and/or Al(OH) 3 ; the HARCPs are characterized by an HARCP aspect ratio of more than about 3; and the LARCPs are characterized by an LARCP aspect ratio of about 1 to about 3.

2 . The separator of claim 1 , wherein:
a Gurley air permeability of the separator coating is in a range of about 7 sec/100 ml to about 60 sec/100 ml.

3 . The separator of claim 2 , wherein:
the Gurley air permeability of the separator coating is in a range of about 7 sec/100 ml to about 40 sec/100 ml.

4 . The separator of claim 1 , wherein:
the thickness of the separator coating is in a range of about 1.0 μm to about 4.0 μm.

5 . The separator of claim 4 , wherein:
the thickness of the separator coating is in a range of about 1.0 μm to about 3.5 μm.

6 . The separator of claim 5 , wherein:
the thickness of the separator coating is in a range of about 1.0 μm to about 3.0 μm.

7 . The separator of claim 1 , wherein:
the mass fraction of the binder is in a range of about 5 wt. % to about 15 wt. %.

8 . The separator of claim 1 , wherein:
an average length of the HARCPs is in a range of about 1.0 μm to about 30.0 μm; and/or an average length of the LARCPs is in a range of about 0.1 μm to about 3.0 μm.

9 . The separator of claim 1 , wherein:
a Brunauer-Emmett-Teller specific surface area (BET-SSA) of the ceramic particles is in a range of about 30 to about 400 m 2 /g.

10 . The separator of claim 1 , wherein:
a particle size distribution of the ceramic particles, as measured by laser particle size distribution analysis (LPSA), exhibits at least a first peak and a second peak in a range of about 0.1 μm to about 8 μm.

11 . The separator of claim 10 , wherein:
the first peak is in a range of about 0.1 μm to about 1.0 μm and the second peak is in a range of about 1 μm to about 8 μm.

12 . The separator of claim 1 , wherein:
the HARCPs are aligned more closely to a longitudinal direction within a plane of the polymer membrane than to a direction perpendicular to the plane.

13 . The separator of claim 1 , wherein:
a puncture strength of the separator is in a range of about 15 to about 30 N; and/or a thermal shrinkage of the separator, after storage at 120° C. for 60 minutes, is in a range of 0.5 to 5.0%; and/or a thermal shrinkage of the separator, after storage at 150° C. for 15 minutes, is in a range of 10 to 25%.

14 . The separator of claim 13 , wherein:
the thermal shrinkage of the separator, after the storage at 120° C. for 60 minutes, is in a range of about 0.5 to about 3.0%.

15 . A lithium-ion battery, comprising:
an anode; a cathode; an electrolyte ionically coupling the anode and the cathode; and the separator of claim 1 disposed in a space between the anode and the cathode.

16 . A method comprising:
(A1) preparing a dispersion comprising (1) ceramic particles comprising a mixture of higher-aspect ratio ceramic particles (HARCPs) and lower-aspect ratio ceramic particles (LARCPs), (2) a binder, and (3) a solvent; and (A2) dispensing the dispersion on a substrate to form a layer and drying the layer to form a separator coating on the substrate, wherein: a thickness of the separator coating is in a range of about 0.5 μm to about 5.0 μm; a mass fraction of the binder in the separator coating is about 20 wt. % or less; the ceramic particles comprise Al 2 O 3 , AlO(OH), and/or Al(OH) 3 ; the HARCPs are characterized by an HARCP aspect ratio of more than about 3; and the LARCPs are characterized by an LARCP aspect ratio of about 1 to about 3; and the substrate comprises a polymer membrane.

17 . The method of claim 16 , wherein:
a Gurley air permeability of the separator coating is in a range of about 7 sec/100 ml to about 60 sec/100 ml.

18 . The method of claim 17 , wherein:
the Gurley air permeability of the separator coating is in a range of about 7 sec/100 ml to about 40 sec/100 ml.

19 . The method of claim 16 , wherein:
the thickness of the separator coating is in a range of about 1.0 μm to about 4.0 μm.

20 . The method of claim 19 , wherein:
the thickness of the separator coating is in a range of about 1.0 μm to about 3.5 μm.

21 . The method of claim 20 , wherein:
the thickness of the separator coating is in a range of about 1.0 μm to about 3.0 μm.

22 . The method of claim 16 , wherein:
the mass fraction of the binder is in a range of about 5 wt. % to about 15 wt. %.

23 . The method of claim 16 , wherein:
an average length of the HARCPs is in a range of about 1.0 μm to about 30.0 μm; and/or an average length of the LARCPs is in a range of about 0.1 μm to about 3.0 μm.

24 . The method of claim 16 , wherein:
a Brunauer-Emmett-Teller specific surface area (BET-SSA) of the ceramic particles is in a range of about 30 to about 400 m 2 /g.

25 . The method of claim 16 , wherein:
a particle size distribution of the ceramic particles, as measured by laser particle size distribution analysis (LPSA), exhibits at least at least a first peak and a second peak in a range of about 0.1 μm to about 8 μm.

26 . The method of claim 25 , wherein:
the first peak is in a range of about 0.1 μm to about 1.0 μm and the second peak is in a range of about 1 μm to about 8 μm.

27 . The method of claim 16 , wherein:
the dispensing of the dispersion is along a machine direction within a plane of the substrate; and the HARCPs are aligned more closely to the machine direction than to a direction perpendicular to the plane.

28 . The method of claim 16 , wherein:
the substrate is in the form of a roll.

29 . A separator comprising the separator coating made according to the method of claim 16 .

30 . A lithium-ion battery, comprising:
an anode; a cathode; an electrolyte ionically coupling the anode and the cathode; and the separator of claim 29 disposed in a space between the anode and the cathode.

Assignees

• Sila Nanotechnologies Inc

Inventors

• Isobe Ryosuke
• Perez De Leon Alexander Carlos
• Wu Yi-Jui
• Ho Alec Sai
• Lynch David Michael
• Owyeung Rachel Elise
• Virgili Justin Michael
• Yushin Gleb Nikolayevich

Classifications

• H01M10/0525

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

• H01M50/451

  comprising layers of only organic material and layers containing inorganic material · CPC title

• H01M50/491

  Porosity · CPC title

• H01M50/403

  Manufacturing processes of separators, membranes or diaphragms · CPC title

• H01M50/446 Primary

  Composite material consisting of a mixture of organic and inorganic materials · CPC title