Methods of lithiating electroactive materials

Patent metadata

Field	Value
Publication number	US-2021175486-A1
Application number	US-201916706331-A
Country	US
Kind code	A1
Filing date	Dec 6, 2019
Priority date	Dec 6, 2019
Publication date	Jun 10, 2021
Grant date	—

Abstract

The present disclosure relates to electroactive materials for use in electrodes of lithium-ion electrochemical cells and methods of making the same, for example, methods for lithiating electroactive materials. A method of lithiating an electroactive material may include dispersing an electroactive material precursor within a room-temperature electrolyte that includes a lithium-based salt and contacting the electrolyte mixture and a lithium source so as to cause the lithium source to ionize and form lithium ions. The lithium ions may react with the electroactive material precursor to form a fully lithiated electroactive material (e.g., greater than 70% of total lithiation). The method further includes, in certain aspects, electrochemically discharging the fully lithiated electroactive material to form a lithiated electroactive material having an optimized lithiation state (e.g., less than or equal to about 40% of a first lithiation state of the fully lithiated electroactive material).

First claim

What is claimed is:

1 . A method for forming a lithiated electroactive material, the method comprising:
dispersing an electroactive material precursor within an electrolyte that includes a lithium-based salt at room temperature to form an electrolyte mixture; and contacting the electrolyte mixture and a lithium source so as to cause the lithium source to ionize and form lithium ions (Li + ), wherein the lithium ions (Li + ) react with the electroactive material precursor in the electrolyte mixture to form the lithiated electroactive material.

2 . The method of claim 1 , wherein after the lithium ions (Li + ) react with the electroactive material precursor in the electrolyte mixture, the lithiated electroactive material is in a first state, and the method further comprises electrochemically discharging the lithiated electroactive material to have less than or equal to about 40% of the total lithium present in the lithiated electroactive material in the first state.

3 . The method of claim 1 , wherein after the lithium ions (Li + ) react with the electroactive material precursor in the electrolyte mixture, the lithiated electroactive material is in a first state represented by the formula Li 4.4x Si, where 0.75≤x≤1, and the method further comprises electrochemically discharging the lithiated electroactive material to a second state represented by the formula Li 4.4x Si, where 0.015≤x≤0.5.

4 . The method of claim 3 , wherein the electroactive material precursor is a silicon powder precursor, in the first state the lithiated electroactive material comprises Li 4.4 Si, and in the second state the lithiated electroactive material comprises Li 0.8 Si.

5 . The method of claim 2 , wherein the method for forming the lithiated electroactive material is a continuous flow process, and the dispersing and contacting occurs in a first container and the electrochemically discharging occurs in a second container, wherein the first and second containers are formed from materials that are non-reactive with the electrolyte mixture.

6 . The method of claim 5 , wherein the first and second containers comprise one or more of stainless steel, nickel, and copper.

7 . The method of claim 5 , wherein the first and second containers are in fluid communication and the lithiated electroactive material flows from the first container to the second container.

8 . The method of claim 5 , wherein the second container includes a counter electrode comprising one or more of graphite, lithium phosphate (Li 3 PO 4 ) (LPO), and lithium titanate (Li 2 TiO 3 ) (LTO).

9 . The method of claim 8 , wherein the counter electrode is disposed within a separator.

10 . The method of claim 8 , wherein the method includes applying a voltage bias to the counter electrode, wherein, upon application of the voltage bias, discharged lithium ions (Li + ) move from the lithiated electroactive particles to the counter electrode so as to form the lithiated electroactive material having the second state, wherein the voltage bias is greater than or equal to about 0.1 V to less than or equal to about 24 V and the voltage bias is applied for greater than or equal to about 1 minute to less than or equal to about 24 hours.

11 . The method of claim 2 , wherein the dispersing and contacting occurs in a container and, prior to the electrochemically discharging, the method further comprises extracting the lithium source from the container and disposing a counter electrode within the container and conducting the electrochemically discharging.

12 . The method of claim 11 , wherein the counter electrode comprises one or more of graphite, lithium phosphate (Li 3 PO 4 ) (LPO), and lithium titanate (Li 2 TiO 3 ) (LTO), and the container comprises one or more of stainless steel, nickel, and copper.

13 . The method of claim 2 , wherein, after the electrochemically discharging, discharged lithium ions (Li + ) are recaptured and recycled.

14 . The method of claim 2 , wherein the method further includes isolating the lithiated electroactive material.

15 . The method of claim 1 , wherein the lithium source coats an interior channel of a channel flow reactor and the electrolyte mixture travels through the channel flow reactor.

16 . The method of claim 1 , wherein the lithium source defines an interior surface of a channel flow reactor and the electrolyte mixture travels through the channel flow reactor.

17 . A method for forming a lithiated electroactive material at room temperature, the method comprising:
dispersing a silicon powder precursor within an electrolyte at a room-temperature electrolyte that comprises a lithium-based salt; contacting the electrolyte mixture and a lithium source so as to cause the lithium source to ionize and form lithium ions (Li + ), wherein the lithium ions (Li + ) react with the silicon powder precursor to form Li 4.4x Si, where 0.75≤x≤1; and applying a voltage bias to a counter electrode in electrical communication with the Li 4.4x Si to cause electrochemical discharge of lithium ions (Li + ) that move from Li 4.4x Si towards the counter electrode to form Li 4.4x Si, where 0.015≤x≤0.5.

18 . The method of claim 17 , wherein the voltage bias is greater than or equal to about 0.1 V to less than or equal to about 24 V and the voltage bias is applied for greater than or equal to about 1 minute to less than or equal to about 24 hours.

19 . The method of claim 17 , wherein the method for forming the lithiated electroactive material is a continuous flow process.

20 . The method of claim 17 , wherein the lithium source defines an interior channel of a channel flow reactor and the electrolyte mixture travels through the channel flow reactor.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Cain Jeffrey D
• Bobel Andrew C
• Pieczonka Nicholas P
• Schmidt Robert D
• Sachdev Anil K
• Verbrugge Mark W

Classifications

• H01M4/139

  Processes of manufacture · CPC title

• H01M10/0525

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

• H01M4/13 Primary

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M4/1395

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

• H01M4/405

  Alloys based on lithium · CPC title