Protective coatings for conversion material cathodes

Patent metadata

Field	Value
Publication number	US-10511012-B2
Application number	US-201615337566-A
Country	US
Kind code	B2
Filing date	Oct 28, 2016
Priority date	Jul 24, 2012
Publication date	Dec 17, 2019
Grant date	Dec 17, 2019

Abstract

Battery systems using coated conversion materials as the active material in battery cathodes are provided herein. Protective coatings may be an oxide, phosphate, or fluoride, and may be lithiated. The coating may selectively isolate the conversion material from the electrolyte. Methods for fabricating batteries and battery systems with coated conversion material are also provided herein.

First claim

What is claimed is:

1. An energy storage device comprising:
a. an anode,
b. an electrolyte, and
c. a cathode comprising:
a plurality of coated electrochemically active material particles, each electrochemically active material particle comprising:
a core comprising a conversion material, and
a coating surrounding the core comprising the conversion material,

wherein the coating selectively isolates the conversion material from the electrolyte,
wherein the electrochemically active material particles have a capacity that is greater than 300 mAh/g;
wherein the coating has a median coating coverage surrounding the core comprising the conversion material that is at least 90% of the surface area of the core comprising the conversion material; and
wherein the core comprising the conversion material comprises conversion material in the charged state;
wherein the conversion material comprises a fluoride of a metal; and wherein the metal is iron, manganese, nickel, copper, or cobalt; wherein the coating surrounding the core comprises lithium oxides, lithium halides, lithium alloys, or combinations thereof.

2. The energy storage device of claim 1 , wherein the device has a capacity when discharged at 1 C that is at least 60% of its capacity when discharged at C/3.

3. The energy storage device of claim 1 , wherein the coating surrounding the core comprises two or more layers, each layer having a thickness between about 0.5 nm and about 15 nm.

4. The energy storage device of claim 1 , wherein the cathode further comprises
an ion conductor, and
a current collector.

5. The energy storage device of claim 4 , wherein the cathode forms a continuous sheet overlapping the electrolyte.

6. The energy storage device of claim 1 , wherein the conversion material comprises nanocrystalline domains having a median size of <20 nm.

7. The energy storage device of claim 6 , wherein the conversion material is a mixture of two metal fluorides.

8. The energy storage device of claim 4 , wherein the conversion material comprises nanocrystalline domains having a median size of <20 nm.

9. The energy storage device of claim 1 , wherein the core comprising conversion material comprises FeF 3 .

10. The energy storage device of claim 1 , wherein the coating completely surrounds the core comprising the conversion material.

Assignees

• Quantumscape Corp

Inventors

• Fasching Rainer
• Han Joseph
• Shan Jon
• Loveness Ghyrn E
• Tulsky Eric
• Holme Timothy

Classifications

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/1395

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

• H01M4/0423

  Physical vapour deposition · CPC title