Gelation reagent for forming gel electrolyte and methods relating thereto

Patent metadata

Field	Value
Publication number	US-11522221-B2
Application number	US-201916725550-A
Country	US
Kind code	B2
Filing date	Dec 23, 2019
Priority date	Dec 23, 2019
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

The present technology relates to gel electrolytes for using in lithium-ion electrochemical cells and methods of forming the same. For example, the method may include adding one or more gelation reagents to an electrochemical cell including one or more liquid electrolyte precursors. The one or more gelation reagents include one or more initiators and one or more crosslinking agents. Each of the one or more initiators may be one of a thermal initiator and an actinic/electron beam initiator. Each of the one or more crosslinking agents may be one of a tridentate alkane and a tetradentate alkane having one or more substitutes including a terminal group represented by:

First claim

What is claimed is:

1. A method of preparing a gel polymer electrolyte for use in an electrochemical cell that cycles lithium ions, wherein the method comprises:
adding a gelation reagent to a liquid electrolyte to form an electrolyte mixture that defines the gel polymer electrolyte, wherein the gelation reagent includes one or more initiators and one or more crosslinking agents, the one or more initiators comprising a thermal initiator selected from the group consisting of: azobisisobutyronitrile (AIBN), 1,1′-azobis(cyclohexanecarbonitrile) (ABCN), benzoyl peroxide (BPO), di-tert-butyl peroxide, and combinations thereof, each of the one or more crosslinking agents is one of a tridentate alkane and a tetradentate alkane having one or more substitutes including a terminal group represented by:

2. The method of claim 1 , wherein the one or more crosslinking agents are selected from the group consisting of: trimethylolpropane triacrylate (TMPTA), pentaerythritol triacrylate, ethoxylated trimethylolpropane triacrylate, alkyloyl-modified dipentaerythritol triacrylate, ethoxylated glycerin triacrylate, pentaerythritol tetraacrylate, di(trimethylolpropane) tetraacrylate, ethoxylated pentaerythritol tetraacrylate, and combinations thereof.

3. The method of claim 2 , wherein the gel polymer electrolyte includes a polymeric backbone defined by the one or more crosslinking agents.

4. The method of claim 1 , wherein after adding the gelation reagent to the liquid electrolyte, the method further comprises heating the electrolyte mixture to a temperature greater than or equal to about 45° C. to less than or equal to about 120° C. for a period greater than or equal to about 5 minutes to less than or equal to about 180 minutes to form the gel polymer electrolyte.

5. The method of claim 1 , wherein the one or more initiators further comprises an actinic/electron beam initiator selected from the group consisting of:
benzophenone, diaryliodonium hexafluoroantimonate, acetophenone, anisoin, benzil, benzoin, 2-benzyl-2-(dimethylamino)-4′-morpholinobutyrophenone, camphorquinone, 4,4′-dihydroxybenzophenone, 4′-ethoxyacetophenone, methybenzoylformate, 2-methyl-4′-(methylthio)-2-morpholinopropiophenone, thioxanthen-9-one, and combinations thereof.

6. The method of claim 1 , wherein the gelation reagent comprises greater than or equal to about 0.1 wt. % to less than or equal to about 10 wt. % of the one or more initiators and a balance of the one or more crosslinking agent.

7. The method of claim 1 , wherein the gel polymer electrolyte comprises greater than or equal to about 1 wt. % to less than or equal to about 99 wt. % of the gelation reagent.

8. The method of claim 1 , wherein the liquid electrolyte comprises:
one or more lithium salts selected from the group consisting of: lithium hexafluorophosphate (LiPF 6 ); lithium perchlorate (LiClO 4 ), lithium tetrachloroaluminate (LiAlCl 4 ), lithium iodide (LiI), lithium bromide (LiBr), lithium thiocyanate (LiSCN), lithium tetrafluoroborate (LiBF 4 ), lithium difluorooxalatoborate (LiBF 2 (C 2 O 4 )) (LiODFB), lithium tetraphenylborate (LiB(C 6 H 5 ) 4 ), lithium bis-(oxalate)borate (LiB(C 2 O 4 ) 2 ) (LiBOB), lithium tetrafluorooxalatophosphate (LiPF 4 (C 2 O 4 )) (LiFOP), lithium nitrate (LiNO 3 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium trifluoromethanesulfonate (LiCF 3 SO 3 ), lithium bis(trifluoromethanesulfonimide) (LiTFSI) (LiN(CF 3 SO 2 ) 2 ), lithium fluorosulfonylimide (LiN(FSO 2 ) 2 ) (LiFSI), lithium fluoroalkylphosphate (LiFAP) (Li 3 O 4 P), and combinations thereof; and
one or more solvents selected from the group consisting of: ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), fluoroethylene carbonate (FEC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl formate, methyl acetate, methyl propionate, γ-butyrolactone, γ-valerolactone, 1,2-dimethoxyethane (DME), 1-2-diethoxyethane, ethoxymethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxolane (DOL), sulfolane, and combinations thereof.

9. The method of claim 1 , wherein the method further includes injecting the gel polymer electrolyte into an electrochemical cell.

10. A method of preparing a gel polymer electrolyte for an electrochemical cell that cycles lithium ions, wherein the method comprises:
contacting a gelation reagent and a liquid electrolyte to form an electrolyte precursor, wherein the gelation reagent includes one or more initiators and one or more crosslinking agents, the one or more initiators comprising a thermal initiator selected from the group consisting of: azobisisobutyronitrile (AIBN), 1,1′-azobis(cyclohexanecarbonitrile) (ABCN), benzoyl peroxide (BPO), di-tert-butyl peroxide, and combinations thereof, and each of the one or more crosslinking agents is one of a tridentate alkane and a tetradentate alkane having one or more substitutes including a terminal group represented by:

introducing the electrolyte precursor into the electrochemical cell; and
curing the electrolyte precursor to form the gel polymer electrolyte.

11. The method of claim 10 , wherein the gel polymer electrolyte includes a polymeric backbone defined by the one or more crosslinking agents, wherein the one or more crosslinking agents are selected from the group consisting of: trimethylolpropane triacrylate (TMPTA), pentaerythritol triacrylate, ethoxylated trimethylolpropane triacrylate, alkyloyl-modified dipentaerythritol triacrylate, ethoxylated glycerin triacrylate, pentaerythritol tetraacrylate, di(trimethylolpropane) tetraacrylate, ethoxylated pentaerythritol tetraacrylate, and combinations thereof.

12. The method of claim 10 , wherein
the electrolyte precursor is cured by heating the electrolyte precursor to a temperature greater than or equal to about 45° C. to less than or equal to about 120° C. for a period greater than or equal to about 5 minutes to less than or equal to about 180 minutes.

13. The method of claim 10 , wherein the one or more initiators further comprises an actinic/electron beam initiator selected from the group consisting of: benzophenone, diaryliodonium hexafluoroantimonate, acetophenone, anisoin, benzil, benzoin, 2-benzyl-2-(dimethylamino)-4′-morpholinobutyrophenone, camphorquinone, 4,4′-dihydroxybenzophenone, 4′-ethoxyacetophenone, methybenzoylformate, 2-methyl-4′-(methylthio)-2-morpholinopropiophenone, thioxanthen-9-one, and combinations thereof.

14. The method of claim 10 , wherein the gelation reagent comprises greater than or equal to about 0.1 wt. % to less than or equal to about 10 wt. % of the one or more initiators and a balance of the one or more crosslinking agent.

15. A method of preparing a gel polymer electrolyte for use in an electrochemical cell that cycles lithium ions, wherein the method comprises:
adding a gelation reagent to a liquid electrolyte to form an electrolyte mixture that defines the gel polymer electrolyte, the gelation reagent comprising one or more initiators and one or more crosslinking agents, each of the one or more initiators being one of a thermal initiator and an actinic/electron beam initiator, each of the one or more crosslinking agents being one of a tridentate alkane and a tetradentate alkane having one or more substitutes including a terminal group represented by:

and

Assignees

• Gm Global Tech Operations Llc

Inventors

• Dai Fang
• Chen Shuru
• Cai Mei

Classifications

• H01M10/0565 Primary

  Polymeric materials, e.g. gel-type or solid-type · CPC title

• C08F222/103

  of trialcohols, e.g. trimethylolpropane tri(meth)acrylate · CPC title

• H01M10/0525

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

• C08F283/06 Primary

  on to polyethers, polyoxymethylenes or polyacetals {(C08F283/004 takes precedence)} · CPC title

• C08K3/32

  Phosphorus-containing compounds · CPC title