Electrolytes for improved performance of cells with high-capacity anodes based on micron-scale moderate volume-changing particles

Patent metadata

Field	Value
Publication number	US-2018205111-A1
Application number	US-201815873850-A
Country	US
Kind code	A1
Filing date	Jan 17, 2018
Priority date	Jan 17, 2017
Publication date	Jul 19, 2018
Grant date	—

Abstract

A metal-ion battery cell is provided that comprises anode and cathode electrodes, a separator, and an electrolyte. The anode electrode may, for example, have a capacity loading in the range of about 2 mAh/cm2 to about 10 mAh/cm2 and comprise anode particles that (i) have an average particle size in the range of about 0.2 microns to about 40 microns, (ii) exhibit a volume expansion in the range of about 8 vol. % to about 180 vol. % during one or more charge-discharge cycles of the battery cell, and (iii) exhibit a specific capacity in the range of about 600 mAh/g to about 2600 mAh/g. The electrolyte may comprise, for example, (i) one or more metal-ion salts and (ii) a solvent composition that comprises one or more low-melting point solvents that each have a melting point below about −70° C. and a boiling point above about +70° C.

First claim

1 . A metal-ion battery cell, comprising:
anode and cathode electrodes, wherein the anode electrode has a capacity loading in the range of about 2 mAh/cm 2 to about 10 mAh/cm 2 and comprises anode particles that (i) have an average particle size in the range of about 0.2 microns to about 40 microns, (ii) exhibit a volume expansion in the range of about 8 vol. % to about 180 vol. % during one or more charge-discharge cycles of the battery cell, and (iii) exhibit a specific capacity in the range of about 600 mAh/g to about 2600 mAh/g; a separator electrically separating the anode electrode and the cathode electrode; and an electrolyte ionically coupling the anode electrode and the cathode electrode, wherein the electrolyte comprises (i) one or more metal-ion salts and (ii) a solvent composition that comprises one or more low-melting point solvents that each have a melting point below about −70° C. and a boiling point above about +70° C.

2 . The battery cell of claim 1 , wherein the average particle size is in the range of about 0.4 microns to about 20 microns.

3 . The battery cell of claim 1 , wherein the anode particles have a specific surface area in the range of about 0.3 m 2 /g to about 60 m 2 /g.

4 . The battery cell of claim 1 , wherein the one or more low-melting point solvents comprise one or more phosphorous-comprising solvents, one or more esters, one or more ethers, one or more fluorinated solvents, or a combination thereof.

5 . The battery cell of claim 4 , wherein the one or more low-melting point solvents comprise the one or more esters.

6 . The battery cell of claim 5 , wherein at least about 50 vol. % of the one or more esters have a carbon backbone with five carbon atoms.

7 . The battery cell of claim 1 , wherein the one or more low-melting point solvents constitute a volume fraction of the solvent composition that is in the range of about 30 vol. % to about 70 vol. %.

8 . The battery cell of claim 7 , wherein the one or more low-melting point solvents constitute a volume fraction of the solvent composition that is in the range of about 40 vol. % to about 60 vol. %.

9 . The battery cell of claim 1 , wherein the solvent composition further comprises two or more regular-melting point solvents, in addition to the one or more low-melting point solvents, that each have a melting point above about −60° C.

10 . The battery cell of claim 9 , wherein the two or more regular-melting point solvents constitute a volume fraction of the solvent composition that is at least about 30 vol. %.

11 . The battery cell of claim 9 , wherein the two or more regular-melting point solvents comprise two or more solvents selected from the group consisting of: carbonates, sulfones, lactones, phosphorus-comprising solvents, silicon-comprising solvents, sulfur-comprising solvents, esters, or a combination thereof.

12 . The battery cell of claim 11 , wherein the two or more regular-melting point solvents comprise one or more linear carbonates and one or more cyclic carbonates.

13 . The battery cell of claim 9 , wherein the two or more regular-melting point solvents comprise a fluorinated solvent that constitutes a volume fraction of the solvent composition that is in the range of about 1 vol. % to about 20 vol. %.

14 . The battery cell of claim 9 , wherein the two or more regular-melting point solvents comprise a phosphorous-based solvent that constitutes a volume fraction of the solvent composition that is in the range of about 0.1 vol. % to about 5 vol. %.

15 . The battery cell of claim 9 , wherein the two or more regular-melting point solvents comprise a vinylene carbonate solvent that constitutes a volume fraction of the solvent composition that is in the range of about 0.1 vol. % to about 3 vol. %.

16 . The battery cell of claim 1 , wherein the one or more metal-ion salts are present in the electrolyte at a concentration in the range of about 1.2M to about 2M.

17 . The battery cell of claim 1 , wherein the one or more metal-ion salts comprise LiPF 6 , LiBOB, LiF SI, or a combination thereof.

18 . The battery cell of claim 1 , wherein the one or more metal-ion salts comprise two or more metal-ion salts.

19 . The battery cell of claim 18 , wherein the two or more metal-ion salts comprise (i) a first metal-ion salt including a first metal ion species and (ii) a second metal-ion salt including a second metal ion species, wherein the first and second metal ion species are the same.

20 . The battery cell of claim 18 , wherein the two or more metal-ion salts comprise (i) a first metal-ion salt including a first metal ion species and (ii) a second metal-ion salt including a second metal ion species, wherein the first and second metal ion species are different.

21 . The battery cell of claim 1 , wherein the battery cell exhibits a charging potential of at least about 4.3 V.

22 . The battery cell of claim 1 , wherein the anode particles are composite particles that comprise silicon.

23 . The battery cell of claim 1 , wherein the anode electrode further comprises a water-soluble binder.

Assignees

• Sila Nanotechnologies Inc

Inventors

• Yushin Gleb
• Ward Ashleigh
• Roberts Gregory

Classifications

• H01M10/052 Primary

  Li-accumulators · CPC title

• H01M10/0561

  the electrolyte being constituted of inorganic materials only · CPC title

• H01M2010/4292

  Aspects relating to capacity ratio of electrodes/electrolyte or anode/cathode · CPC title

• H01M2300/0028

  characterised by the solvent · CPC title

• H01M2004/027

  Negative electrodes · CPC title