Thermally conductive lithium ion electrodes and batteries

Patent metadata

Field	Value
Publication number	US-9991512-B2
Application number	US-201514790449-A
Country	US
Kind code	B2
Filing date	Jul 2, 2015
Priority date	Apr 16, 2015
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

A thermally conductive electrochemical cell comprises a lithium ion-containing liquid electrolyte contacting a cathode and anode. The cathode and anode are in the form of electroactive sheets separated from each other by a membrane that is permeable to the electrolyte. One or more of the cathode and anode comprises two or more layers of carbon nanotubes, one of which layers includes electrochemically active nanoparticles and/or microparticles disposed therein or deposited on the nanotubes thereof. The majority of the carbon nanotubes in each of the layers are oriented generally parallel to the layers. Optionally, one or more of the layers includes an additional carbon material such as graphene, nanoparticulate diamond, microparticulate diamond, and a combination thereof.

First claim

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A lithium ion electrochemical cell comprising:
a lithium ion-containing liquid electrolyte contacting a cathode and an anode that are separated from each other by a membrane that is permeable to the electrolyte;
the cathode and anode each comprising a sheet of at least one electrochemically active material, in which one or more of the cathode and anode comprise a first layer of carbon nanotubes, and a second layer of carbon nanotubes contacting the first layer on one side thereof;
wherein:
the carbon nanotubes in each of the layers have an exterior surface, an interior surface defining a generally hollow interior space therein, a length, and a diameter, in which the length is greater than the diameter;
at least a portion of the carbon nanotubes of the second layer comprise electroactive nanoparticles, electroactive microparticles, or a combination thereof adhering to the exterior surfaces of the carbon nanotubes of the second layer;
the majority of the carbon nanotubes in each of the layers are oriented, lengthwise, generally parallel to the layers; and
the electroactive nanoparticles and microparticles comprise one or more electrochemically active material selected from the group consisting of a metal oxide, a lithium metal oxide, a metal sulfide, a metal nitride, a metal silicide, a metal aluminide, a metal phosphide, a lithium metal phosphate, an intermetallic compound of a transition metal with a non-transition metal element, and intermetallic alloy of a transition metal with a non-transition metal element wherein the non-transition metal element is selected from the group consisting of tin, antimony, and a combination thereof.

2. The electrochemical cell of claim 1 , wherein the carbon nanotubes of each layer comprise multi-walled carbon nanotubes.

3. The electrochemical cell of claim 2 , wherein the carbon nanotubes of each layer independently have an average tube diameter in the range of about 1.5 to about 15 nm, an average tube wall thickness in the range of about 1 to about 6 nm, and lengths in the range of about 0.5 to about 200 micrometers (μm).

4. The electrochemical cell of claim 3 , wherein the majority of the carbon nanotubes of each layer have lengths in the range of about 80 to about 150 μm.

5. The electrochemical cell of claim 4 , wherein at least a portion of the carbon nanotubes of each layer have lengths in the range of about 2 to about 10 μm.

6. The electrochemical cell of claim 1 , wherein one or more of the layers includes an additional carbon material admixed therewith.

7. The electrochemical cell of claim 6 , wherein the additional carbon material comprises a material selected from the group consisting of graphene, nanoparticulate diamond, microparticulate diamond, and a combination thereof.

8. The electrochemical cell of claim 1 , wherein one or more of the layers comprises about 20 to about 50 percent by volume of nanoparticulate diamond, microparticulate diamond, or a combination thereof.

9. The electrochemical cell of claim 1 , wherein each of the layers independently has an average thickness in the range of about 15 to about 50 μm.

10. The electrochemical cell of claim 1 , wherein the electroactive nanoparticles comprise hollow γ-Fe 2 O 3 nanoparticles comprising a crystalline shell of γ-Fe 2 O 3 including iron cation vacancies within the crystal structure thereof and defining a cavity within the nanoparticles; and the electroactive microparticles comprise, in a fully discharged state, a lithium metal oxide of formula LiMO 2 , wherein M comprises one or more first row transition metals.

11. The electrochemical cell of claim 10 , wherein the first row transition metals comprise one or more metals selected from the group consisting of Ni, Co and Mn.

12. The electrochemical cell of claim 10 , wherein the first row transition metals comprise Ni, Co and Mn in substantially equal atomic proportions.

13. The electrochemical cell of claim 10 , wherein lithium ions are intercalated within the cation vacancies of the hollow γ-Fe 2 O 3 nanoparticles.

14. The electrochemical cell of claim 10 , wherein the hollow γ-Fe 2 O 3 nanoparticles have an average particle size in the range of about 3.5 to about 17 nm, and individual nanoparticles comprise a crystalline γ-Fe 2 O 3 shell having an average thickness in the range of about 1.1 to about 6 nm.

15. A lithium ion electrochemical cell comprising:
a lithium ion-containing liquid electrolyte contacting a cathode and an anode that are separated from each other by a membrane that is permeable to the electrolyte;
the cathode and anode each comprising a sheet containing at least one electrochemically active material; one or more of the cathode and anode comprising a first layer of carbon nanotubes, and a second layer of carbon nanotubes contacting the first layer on one side thereof;
wherein:
the carbon nanotubes in each of the layers have an exterior surface, an interior surface defining a generally hollow interior space therein, a length, and a diameter, in which the length is greater than the diameter;
electroactive nanoparticles, electroactive microparticles, or a combination thereof are admixed with the carbon nanotubes of the second layer;
the majority of the carbon nanotubes in each of the layers are oriented, lengthwise, generally parallel to the layers;
and
the electroactive nanoparticles and microparticles comprise one or more electrochemically active material selected from the group consisting of a metal oxide, a lithium metal oxide, a metal sulfide, a metal nitride, a metal silicide, a metal aluminide, a metal phosphide, a lithium metal phosphate, an intermetallic compound of a transition metal with a non-transition metal element, and intermetallic alloy of a transition metal with a non-transition metal element wherein the non-transition metal element is selected from the group consisting of tin, antimony, and a combination thereof.

16. The electrochemical cell of claim 15 , wherein the carbon nanotubes of each layer are multi-walled carbon nanotubes.

17. The electrochemical cell of claim 15 , wherein the carbon nanotubes of each layer independently have an average tube diameter in the range of about 1.5 to about 15 nm, an average tube wall thickness in the range of about 1 to about 6 nm, and lengths in the range of about 0.5 to about 200 μm.

18. The electrochemical cell of claim 17 , wherein the majority of the carbon nanotubes of each layer have lengths in the range of about 80 to about 150 μm.

19. The electrochemical cell of claim 18 , wherein at least a portion of the carbon nanotubes of each layer have lengths in the range of about 2 to about 10 μm.

20. The electrochemical cell of claim 15 , wherein one or more of the layers includes an additional carbon material admixed therewith, and wherein the additional carbon material comprises graphene, nanoparticulate diamond, microparticulate diamond, or a combination thereof.

21. The electrochemical cell of claim 15 , wherein the electroactive nanoparticles comprise hollow γ-Fe 2 O 3 nanoparticles comprising a crystalline shell of γ-Fe 2 O 3 including iron cation vacancies within the crystal structure thereof and defining a cavity within the nanoparticles; and the electroactive microparticles comprise, in a fully discharged state, a lithium metal oxide of formula LiMO 2 , wherein M comprises one or more first row transition metals.

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Assignees

• Uchicago Argonne Llc

Inventors

• Shevchenko Elena
• Sumant Anirudha V
• Balandin Alexander
• Koo Bonil
• Johnson Christopher
• Rajh Tijana
• Lee Eungje

Classifications

• H01M4/625

  Carbon or graphite · CPC title

• H01M4/366 Primary

  as layered products · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title