In-situ polymerization to protect lithium metal electrodes

Patent metadata

Field	Value
Publication number	US-11515538-B2
Application number	US-201916599714-A
Country	US
Kind code	B2
Filing date	Oct 11, 2019
Priority date	Oct 11, 2019
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

An electrode including an electrode active material including lithium (Li) and a polymer layer coating at least a portion of the electrode active material is provided. The polymer layer includes a polymerization product of a monomer having Formula I:

where R 1 and R 2 are independently an aryl or a branched or unbranched C 1 -C 10 alkyl and X 1 and X 2 are independently chlorine (Cl), bromine (Br), or iodine (I).

First claim

What is claimed is:

1. An electrode comprising:
an electrode active material comprising lithium (Li); and
a polymer layer coating at least a portion of the electrode active material,
wherein the polymer layer comprises a polymerization product of a monomer having Formula I:

where R 1 and R 2 are independently an aryl or a branched or unbranched C 1 -C 10 alkyl; and
X 1 and X 2 are independently chlorine (Cl), bromine (Br), or iodine (I); and
wherein the polymerization product comprises a polymer of Formula II:

where R 1 or R 2 are defined in regard to Formula I;
R 3 is X 1 , X 2 , —OH from a surface of the electrode active material, or —OLi from a surface of the electrode active material;
R 4 is Li from a surface of the electrode active material, hydrogen (H) from a surface of the electrode active material, or —SiR 1 R 2 X 1/2 ; and
n is an integer greater than 2.

2. The electrode according to claim 1 , wherein at least one of R 1 or R 2 is phenyl.

3. The electrode according to claim 2 , wherein the phenyl is substituted with at least one C 1 -C 10 alkyl, a halide, or combinations thereof.

4. The electrode according to claim 1 , wherein at least one of R 1 or R 2 is (diphenylphosphino)phenyl.

5. The electrode according to claim 1 , wherein at least one of R 1 or R 2 is fluorenyl.

6. The electrode according to claim 1 , wherein at least one of R 1 or R 2 is C 1 -C 10 alkyl.

7. The electrode according to claim 1 , wherein the monomer is selected from the group consisting of dichlorodiphenylsilane, dichloro(methyl)phenylsilane, di-p-tolyldichlorosilan, bis[2-(diphenylphosphino)phenyl]dichlorosilane, bis(4-butylphenyl)-dichlorosilane, dimesityldichlorosilane, and bis(9H-fluoren-9-yl)dichlorosilane

8. The electrode according to claim 1 , wherein the polymer layer is substantially free of pores.

9. The electrode according to claim 1 , further comprising a current collector, wherein the electrode active material is disposed on the current collector.

10. The electrode according to claim 1 , wherein the electrode active material is Li metal.

11. The electrode according to claim 1 , wherein the electrode active material comprises a Li alloy comprising the Li and at least one of aluminum (Al), tin (Sn), antimony (Sb), germanium (Ge), or silicon (Si).

12. An electrochemical cell comprising the electrode according to claim 1 .

13. The electrochemical cell according to claim 12 , wherein the electrode is an anode positioned in the electrochemical cell that cycles Li ions.

14. An electrode comprising:
an electrode active material comprising lithium (Li); and
a polymer layer coating at least a portion of the electrode active material,
wherein the polymer layer comprises a polymer having Formula II:

where R 1 and R 2 are independently an aryl;
R 3 is chlorine (Cl), bromine (Br), iodine (I), —OH from a surface of the electrode active material, or —OLi from a surface of the electrode active material;
R 4 is Li from a surface of the electrode active material, hydrogen (H) from a surface of the electrode active material, or —SiR 1 R 2 X 1/2 ; and
n is an integer greater than 2.

15. The electrode according to claim 14 , wherein the electrode is an anode and R 1 and R 2 are the same.

16. The electrode according to claim 15 , wherein R 1 and R 2 are both phenyl, (diphenylphosphino)phenyl, tolyl, butylphenyl, fluorenyl, or mesityl.

17. A method of fabricating an electrode, the method comprising:
applying a monomer solution to at least one surface of an electrode active material comprising lithium (Li), the monomer solution comprising a monomer having Formula I:

where R 1 and R 2 are independently an aryl or a branched or unbranched C 1 -C 10 alkyl, and
X 1 and X 2 are independently chlorine (Cl), bromine (Br), or iodine (I); and
polymerizing the monomer to form a polymer layer coating comprising a polymerization product on at least a portion of the electrode active material, wherein the polymerization product comprises a polymer of Formula II:

where R 1 or R 2 are defined in regard to Formula I;
R 3 is X 1 , X 2 , —OH from a surface of the electrode active material, or —OLi from a surface of the electrode active material;
R 4 is Li from a surface of the electrode active material, hydrogen (H) from a surface of the electrode active material, or —SiR 1 R 2 X 1/2 ; and
n is an integer greater than 2.

18. The method according to claim 17 , wherein the applying comprises contacting the at least one surface of the electrode active material with the monomer solution for a time of greater than or equal to about 30 seconds to less than or equal to about 10 minutes, during which time the polymerizing occurs spontaneously to form the polymer layer.

19. The method according to claim 17 , further comprising:
rinsing the polymer layer with an inert solvent.

20. The method according to claim 17 , wherein R 1 and R 2 are the same and X 1 and X 2 are the same.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Li Binsong
• Xiao Xingcheng

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/1395

  of electrodes based on metals, Si or alloys · CPC title

• C08G77/80

  Siloxanes having aromatic substituents, e.g. phenyl side groups · CPC title

• C09D183/04

  Polysiloxanes · CPC title