Multi-phase electrolyte lithium batteries

Patent metadata

Field	Value
Publication number	US-10158109-B2
Application number	US-201615164819-A
Country	US
Kind code	B2
Filing date	May 25, 2016
Priority date	Feb 13, 2008
Publication date	Dec 18, 2018
Grant date	Dec 18, 2018

Abstract

Electrode assemblies for use in electrochemical cells are provided. The negative electrode assembly includes negative electrode active material and an electrolyte chosen specifically for its useful properties in the negative electrode. Such properties include reductive stability and ability to accommodate expansion and contraction of the negative electrode active material. Similarly, the positive electrode assembly includes positive electrode active material and an electrolyte chosen specifically for its useful properties in the positive electrode. These properties include oxidative stability and the ability to prevent dissolution of transition metals used in the positive electrode active material. A third electrolyte can be used as separator between the negative electrode and the positive electrode. A cell is constructed with a cathode that includes a fluorinated electrolyte which does not penetrate into the solid-state polymer electrolyte separator between it and the lithium-based anode. Such an assembly improves charge transport properties without compromising the strength and durability of the separator.

First claim

We claim:

1. An electrochemical cell, comprising:
a negative electrode configured to absorb and release alkali metal ions;
an electrolyte layer in contact with the negative electrode, the electrolyte layer comprising a first block copolymer electrolyte and a first salt comprising the alkali metal; and
a positive electrode comprising positive electrode active material, binder, a liquid electrolyte and optional electronically conducting carbon;
wherein the liquid electrolyte comprises a fluorinated liquid and a second salt comprising the alkali metal, the liquid electrolyte immiscible with the first block copolymer electrolyte.

2. The electrochemical cell of claim 1 wherein the negative electrode is a metal foil comprising the alkali metal.

3. The electrochemical cell of claim 2 wherein the alkali metal comprises lithium.

4. The electrochemical cell of claim 1 wherein the negative electrode comprises negative electrode active material particles, a negative electrode electrolyte, and optional binder.

5. The electrochemical cell of claim 4 wherein the negative electrode electrolyte comprises a liquid electrolyte that is immiscible with the first block copolymer electrolyte.

6. The electrochemical cell of claim 5 wherein the liquid electrolyte is selected from the group consisting of ethers, alkyl carbonates, ionic liquids, and mixtures thereof.

7. The electrochemical cell of claim 4 wherein the negative electrode electrolyte comprises a second block copolymer electrolyte wherein the second block copolymer electrolyte is immiscible with the first block copolymer electrolyte.

8. The electrochemical cell of claim 1 wherein the positive electrode active material is selected from the group consisting of lithium metal oxides, lithium metal phosphates, elemental sulfur, sulfur composites with carbon, and sulfur composites with pyrolyzed polymer.

9. The electrochemical cell of claim 1 wherein a first block of the first block copolymer is ionically conductive and is selected from the group consisting of polyethers, polyamines, polyimides, polyamides, poly alkyl carbonates, polynitriles, polysiloxanes, polyphosphazines, polyolefins, polydienes, and combinations thereof.

10. The electrochemical cell of claim 1 wherein a first block of the first block copolymer comprises an ionically-conductive comb polymer, which comb polymer comprises a backbone and pendant groups.

11. The electrochemical cell of claim 10 wherein the backbone comprises one or more selected from the group consisting of polysiloxanes, polyphosphazines, polyethers, polydienes, polyolefins, polyacrylates, polymethacrylates, and combinations thereof.

12. The electrochemical cell of claim 10 wherein the pendants comprise one or more selected from the group consisting of oligoethers, substituted oligoethers, nitrile groups, sulfones, thiols, polyethers, polyamines, polyimides, polyamides, alkyl carbonates, polynitriles, other polar groups, and combinations thereof.

13. The electrochemical cell of claim 1 wherein a second block of the first block copolymer is selected from the group consisting of polystyrene, hydrogenated polystyrene, polymethacrylate, poly(methyl methacrylate), polyvinylpyridine, polyvinylcyclohexane, polyimide, polyamide, polypropylene, polyolefins, poly(t-butyl vinyl ether), poly(cyclohexyl methacrylate), poly(cyclohexyl vinyl ether), poly(t-butyl vinyl ether), polyethylene, polyfluorocarbons, polyvinylidene fluoride, and copolymers that contain styrene, methacrylate, and/or vinylpyridine.

14. The electrochemical cell of claim 1 wherein the fluorinated liquid comprises one or more selected from the group consisting of perfluoropolyethers, mono- or diol-terminated perfluoropolyethers, alkylcarbonate-terminated perfluoropolyethers, alkylcarbamate-terminated perfluoropolyethers, poly(perfluoropolyether)acrylates, poly(perfluoropolyether)methacrylates, polysiloxanes with pendant fluorinated groups, and poly(perfluoropolyether)glycidyl ethers.

15. The electrochemical cell of claim 1 wherein the fluorinated liquid comprises:
first polymers selected from the group consisting of polymerized versions of perfluoropolyether-acrylates, -methacrylates, and -glycidyl ethers; and
second polymers selected from the group consisting of polymerized versions of acrylates, methacrylates, or glycidyl ethers;
wherein the first polymers are copolymerized with the second polymers; and
wherein the second polymers comprise less than 10 wt % of the fluorinated liquid.

16. The electrochemical cell of claim 1 wherein the fluorinated liquid further comprises one or more additives selected from the group consisting of cyclic organic carbonates, cyclic acetals, organic phosphates, cyclic organic sulfates, and cyclic organic sulfonates.

17. The electrochemical cell of claim 1 wherein the positive electrode further comprises a polymer matrix into which the fluorinated liquid is absorbed to form a polymer gel electrolyte.

18. The electrochemical cell of claim 1 , further comprising a separator electrolyte layer between the electrolyte layer and the positive electrode, the separator electrolyte layer comprising an electrolyte different the first block copolymer electrolyte.

19. The electrochemical cell of claim 18 wherein the separator electrolyte is selected from the group consisting of ceramic electrolytes, polymer electrolytes, and block copolymer electrolytes.

20. An electrochemical cell, comprising:
a negative electrode comprising an alkali metal film;
a separator layer in contact with the negative electrode, the separator layer comprising a block copolymer electrolyte and a first salt comprising the alkali metal; and
a positive electrode comprising positive electrode active material, binder and a liquid electrolyte comprising a fluorinated liquid and a second salt comprising the alkali metal;
wherein the liquid electrolyte immiscible with the block copolymer electrolyte.

21. An electrochemical cell, comprising:
a negative electrode comprising a film of lithium metal;
a separator layer in contact with the negative electrode, the separator layer comprising a block copolymer electrolyte and a first lithium salt; and
a positive electrode comprising nickel cobalt aluminum oxide particles, binder, a second lithium salt, and a liquid electrolyte comprising a fluorinated liquid;
wherein the liquid electrolyte is immiscible with the block copolymer electrolyte.

Assignees

• Seeo Inc
• Seeo Inc

Inventors

• Eitouni Hany Basam
• Pratt Russell Clayton

Classifications

• H01M2300/0088

  Composites · CPC title

• H01M4/621

  Binders · CPC title

• H01M2300/0082

  Organic polymers · CPC title

• H01M4/625

  Carbon or graphite · CPC title

• H01B1/122

  Ionic conductors · CPC title