Methods of pre-lithiating electrodes

Patent metadata

Field	Value
Publication number	US-2021066704-A1
Application number	US-201916559132-A
Country	US
Kind code	A1
Filing date	Sep 3, 2019
Priority date	Sep 3, 2019
Publication date	Mar 4, 2021
Grant date	—

Abstract

The present disclosure provides methods of compensation for capacity loss resulting from cycle-induced lithium consumption in an electrochemical cell including at least one electrode. Such methods may include adding a lithiation additive to the at least one electrode so as to create a lithium source. The lithium source compensates for cycle-induced lithiation loss such that the electrochemical cell having the lithiation additive experiences total capacity losses of less than or equal to about 5% of an initial capacity prior to cycling of lithium. The lithiation additive includes a lithium silicate represented by the formula Li u H r , where H r =Li y-u SiO z and where 0≤y≤3.75 and 0≤z≤2 and u is a useable portion of y, 0≤u≤y. The lithium source may include z/4 Li 4 SiO 4 and Li m Si, where 0≤m≤4.4.

First claim

1 . A method of compensation for capacity loss resulting from cycle-induced lithium consumption in an electrochemical cell including at least one electrode, the method comprising:
adding a lithiation additive to the at least one electrode to create a lithium source that compensates for cycle-induced lithiation loss that occurs when lithium is cycled in the electrochemical cell such that the electrochemical cell experiences a total capacity loss of less than or equal to about 5% of an initial capacity prior to cycling of lithium in the electrochemical cell, wherein the lithiation additive comprises a lithium silicate represented by the formula Li u H r , wherein H r =Li y-u SiO z and wherein 0≤y≤3.75 and 0≤z≤2 and u is a useable portion of y, 0≤u≤y.

2 . The method of claim 1 , wherein the lithium source comprises z/4 Li 4 SiO 4 and Li m Si, where 0≤m≤4.4.

3 . The method of claim 1 , wherein the at least one electrode includes greater than or equal to about 1 wt. % to less than or equal to about 50 wt. % of the lithiation additive.

4 . The method of claim 1 , wherein the method further includes combining the lithiation additive with an electroactive material and a current collector in an environment comprising oxygen that is substantially free of water and has a dew point of greater than or equal to about −100° C. to less than or equal to about 0° C.

5 . The method of claim 4 , wherein the combining includes mixing greater than or equal to about 1 wt. % to less than or equal to about 50 wt. % of the lithiation additive with greater than or equal to about 50 wt. % to less than or equal to about 95 wt. % of electroactive material and disposing the mixture on a first surface of the current collector.

6 . The method of claim 4 , wherein the combining includes forming a lithiation layer comprising the lithiation additive adjacent to the current collector and forming an electroactive layer on one or more exposed surfaces of the lithiation layer.

7 . The method of claim 6 , wherein the lithiation layer has a thickness greater than or equal to about 10 nm to less than or equal to about 10 μm; and the electroactive layer has a thickness greater than or equal to about 500 nm to less than or equal to about 200 nm.

8 . The method of claim 4 , wherein the electroactive material is selected from the group consisting of: lithium, silicon, silicon oxide, graphite, graphene, carbon nanotubes, lithium titanium oxide (Li 4 Ti 5 O 12 ), tin (Sn), vanadium oxide (V 2 O 5 ), tin oxide (SnO), titanium dioxide (TiO 2 ), titanium niobium oxide (Ti x Nb y O z , where 0≤x≤2, 0≤y≤24, and 0≤z≤64), iron sulfide (FeS), and combinations thereof.

9 . The method of claim 1 , wherein the method further includes cycling lithium in the electrochemical cell.

10 . A method of forming a pre-lithiated electrode for incorporation into an electrochemical cell, the method comprising:
combining a lithiation additive with an electroactive material and a current collector in an environment comprising oxygen that is substantially free of water and has a dew point of greater than or equal to about −100° C. to less than or equal to about 0° C., wherein the lithiation additive comprises a lithium silicate represented by the formula Li u H r , wherein H r =Li y-u SiO z and wherein 0≤y≤3.75 and 0≤z≤2 and u is a useable portion of y, 0≤u≤y.

11 . The method of claim 10 , wherein the combining includes mixing greater than or equal to about 1 wt. % to less than or equal to about 50 wt. % of the lithiation additive with greater than or equal to about 50 wt. % to less than or equal to about 95 wt. % of electroactive material and disposing the mixture on a first surface of the current collector.

12 . The method of claim 10 , wherein the combining includes forming a lithiation layer comprising the lithiation additive adjacent to the current collector and forming an electroactive layer on one or more exposed surfaces of the lithiation layer.

13 . The method of claim 12 , wherein the lithiation layer has a thickness greater than or equal to about 10 nm to less than or equal to about 20 μm; and the electroactive layer has a thickness greater than or equal to about 500 nm to less than or equal to about 200 μm.

14 . The method of claim 10 , wherein the electroactive material is selected from the group consisting of: lithium, silicon, silicon oxide, graphite, graphene, carbon nanotubes, lithium titanium oxide (Li 4 Ti 5 O 12 ), tin (Sn), vanadium oxide (V 2 O 5 ), tin oxide (SnO), titanium dioxide (TiO 2 ), titanium niobium oxide (Ti x Nb y O z , where 0≤x≤2, 0≤y≤24, and 0≤z≤64), iron sulfide (FeS), and combinations thereof.

15 . The method of claim 10 , wherein the lithiation additive comprises a lithium source including z/4 Li 4 SiO 4 and Li m Si, wherein 0≤m≤4.4,
and the electrode has a total capacity loss after a first cycle of less than or equal to about 5% as compared to an initial capacity prior to cycling of lithium in the electrochemical cell.

16 . A method of forming a pre-lithiated electrode for an electrochemical cell, the method comprising:
forming a lithiation layer comprising a lithiation additive adjacent a current collector in an environment comprising oxygen that is substantially free of water and has a dew point of greater than or equal to about −100° C. to less than or equal to about 0° C., wherein the lithiation additive comprises a lithium silicate represented by the formula Li u H r , wherein H r =Li y-u SiO z and wherein 0≤y≤3.75 and 0≤z≤2 and u is a useable portion of y, 0≤u≤y; and forming an electroactive layer on one or more exposed surfaces of the lithiation layer.

17 . The method of claim 16 , wherein the lithiation layer has a thickness greater than or equal to about 10 nm to less than or equal to about 20 μm and comprises a lithium source comprising z/4 Li 4 SiO 4 and Li m Si and 0≤m≤4.4.

18 . The method of claim 16 , wherein the electroactive layer has a thickness greater than or equal to about 500 nm to less than or equal to about 200 μm and the electroactive layer includes one or more electroactive materials selected from the group consisting of: lithium, silicon, silicon oxide, graphite, graphene, carbon nanotubes titanium oxide (Li 4 Ti 5 O 12 ), tin (Sn), vanadium oxide (V 2 O 5 ), tin oxide (SnO), titanium dioxide (TiO 2 ), titanium niobium oxide (Ti x Nb y O z , where 0≤x≤2, 0≤y≤24, and 0≤z≤64), iron sulfide (FeS), and combinations thereof.

19 . The method of claim 18 , wherein the pre-lithiated electrode comprises greater than or equal to about 1 wt. % to less than or equal to about 50 wt. % of the lithiation additive and greater than or equal to about 1 wt. % to less than or equal to about 95 wt. % of the one or more electroactive materials.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Verbrugge Mark W
• Xiao Xingcheng
• Xu Jiagang

Classifications

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M10/0525 Primary

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

• H01M10/058

  Construction or manufacture · CPC title

• H01M10/4235

  Safety or regulating additives or arrangements in electrodes, separators or electrolyte (H01M10/4242 takes precedence) · CPC title