Prelithiated thermally stable separator

Patent metadata

Field	Value
Publication number	US-2025105445-A1
Application number	US-202318471346-A
Country	US
Kind code	A1
Filing date	Sep 21, 2023
Priority date	Sep 21, 2023
Publication date	Mar 27, 2025
Grant date	—

Abstract

A prelithiated separator for use in an electrochemical cell. The prelithiated separator includes a base film including a polymer having a melting point greater than 180° C.; a ceramic directly contacting the base film; and lithium on an outer surface of the prelithiated separator.

First claim

What is claimed is:

1 . A prelithiated separator for use in an electrochemical cell, the prelithiated separator comprising:
a base film comprising a polymer having a melting point greater than 180° C.; a ceramic directly contacting the polymer; and lithium on an outer surface of the prelithiated separator.

2 . The prelithiated separator of claim 1 , wherein the polymer having the melting point greater than 180° C. comprises a polyaramid, a polyimide, polyethylene terephthalate, polytetrafluoroethylene, a polyimide nanofiber nonwoven, a nano-sized Al 2 O 3 and poly(lithium 4-styrenesulfonate)-coated polyethylene membrane, a SiO 2 -coated polyethylene, a co-polyimide-coated polyethylene, a polyetherimide, bisphenol-acetone diphthalic anhydride, para-phenylenediamine, expanded polytetrafluoroethylene reinforced polyvinylidenefluoride-hexafluoropropylene, or a combination thereof.

3 . The prelithiated separator of claim 1 , wherein the ceramic comprises Al 2 O 3 , SiO 2 , ZrO 2 , TiO 2 , lithium titanate, lithiated zeolite, zeolite, MgO, boehmite, or a combination thereof.

4 . The prelithiated separator of claim 1 , wherein a thickness of the lithium compensates for capacity loss during a first cycle of an electrochemical cell comprising the prelithiated separator.

5 . The prelithiated separator of claim 1 , wherein the lithium is on one surface of the base film.

6 . The prelithiated separator of claim 1 , wherein the ceramic directly contacting the polymer comprises a mixture of the ceramic and the polymer.

7 . The prelithiated separator of claim 1 , wherein:
the ceramic directly contacting the polymer comprises a ceramic layer directly on the base film; and the lithium on the outer surface of the prelithiated separator comprises lithium directly on the ceramic layer.

8 . The prelithiated separator of claim 7 , wherein:
the ceramic layer directly on the base film comprises
a first ceramic layer directly on a first surface of the base film, and
a second ceramic layer directly on a second surface of the base film, the second surface of the base film being opposite the first surface of the base film; and
the lithium directly on the ceramic layer comprises
a first lithium layer directly on the first ceramic layer, and
a second lithium layer directly on the second ceramic layer.

9 . The prelithiated separator of claim 7 , wherein the ceramic layer is exposed at an edge of the base film.

10 . A method of forming a prelithiated separator, the method comprising:
depositing a ceramic directly on a base film comprising a polymer having a melting point greater than 180° C.; and depositing lithium directly on the ceramic to form the prelithiated separator.

11 . The method of claim 10 , wherein depositing the lithium comprises thermal evaporation, sputtering, ion beam deposition, or a combination thereof.

12 . The method of claim 10 , wherein depositing the lithium comprises a processing temperature less than the melting point of the polymer.

13 . The method of claim 10 , wherein the polymer having the melting point greater than 180° C. comprises a polyaramid, a polyimide, polyethylene terephthalate, polytetrafluoroethylene, a polyimide nanofiber nonwoven, a nano-sized Al 2 O 3 and poly(lithium 4-styrenesulfonate)-coated polyethylene membrane, a SiO 2 -coated polyethylene, a co-polyimide-coated polyethylene, a polyetherimide, bisphenol-acetone diphthalic anhydride, para-phenylenediamine, expanded polytetrafluoroethylene reinforced polyvinylidenefluoride-hexafluoropropylene, or a combination thereof.

14 . The method of claim 10 , wherein the ceramic comprises Al 2 O 3 , SiO 2 , ZrO 2 , TiO 2 , lithium titanate, lithiated zeolite, zeolite, MgO thereof.

15 . The method of claim 10 , wherein depositing the lithium directly on the ceramic comprises depositing the lithium to a calculated thickness to compensate for capacity loss during a first cycle of an electrochemical cell comprising the prelithiated separator.

16 . The method of claim 10 , wherein depositing the lithium directly on the ceramic comprises depositing the lithium on one surface of the base film.

17 . The method of claim 10 , wherein:
depositing the ceramic directly on a base film comprises
depositing a first ceramic layer directly on a first surface of the base film, and
depositing a second ceramic layer directly on a second surface of the base film, the second surface of the base film being opposite the first surface of the base film; and
depositing lithium directly on the ceramic comprises
depositing a first lithium layer directly on the first ceramic layer, and
depositing a second lithium layer directly on the second ceramic layer.

18 . The method of claim 10 , wherein depositing the lithium directly on the ceramic comprises retaining an exposed area of the ceramic at an edge of the base film.

19 . A method of forming a prelithiated separator, the method comprising:
forming a base film comprising a polymer having a melting point greater than 180° C. and a ceramic; and depositing lithium directly on an outer surface of the base film to form the prelithiated separator.

20 . The method of claim 19 , wherein:
the polymer having the melting point greater than 180° C. comprises a polyaramid, a polyimide, polyethylene terephthalate, polytetrafluoroethylene, a polyimide nanofiber nonwoven, a nano-sized Al 2 O 3 and poly(lithium 4-styrenesulfonate)-coated polyethylene membrane, a SiO 2 -coated polyethylene, a co-polyimide-coated polyethylene, a polyetherimide, bisphenol-acetone diphthalic anhydride, para-phenylenediamine, expanded polytetrafluoroethylene reinforced polyvinylidenefluoride-hexafluoropropylene, or a combination thereof; and the ceramic comprises Al 2 O 3 , SiO 2 , ZrO 2 , TiO 2 , lithium titanate, lithiated zeolite, zeolite, MgO thereof.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Xiao Xingcheng
• Cai Mei

Classifications

• H01M50/443

  Particulate material · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M50/431

  Inorganic material · CPC title

• H01M50/457

  comprising three or more layers · CPC title

• H01M50/451

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