Composite separator and electrolyte for solid state batteries

Patent metadata

Field	Value
Publication number	US-2016141718-A1
Application number	US-201514938375-A
Country	US
Kind code	A1
Filing date	Nov 11, 2015
Priority date	Nov 14, 2014
Publication date	May 19, 2016
Grant date	—

Abstract

Separator and electrolyte composites are disclosed. The composites include a porous self-supporting separator film between or adjacent one or two electrolyte films. The electrolyte films may contain a glyme or mixture of glymes, LiX salt and complexing agent, such as PEO. The porous self-supporting separator film may be used dry or wetted with a liquid electrolyte composition. Solid state batteries using the described separator and electrolyte composites in combination with an anode and a cathode are also disclosed.

First claim

1 . A composite separator and electrolyte for an electrochemical cell comprising:
a porous self-supporting separator film, the porous self-supporting film having a first major surface and a second major surface; at least one electrolyte film contacting the first major surface of the porous self-supporting film, the at least one electrolyte film comprising from 0 to 80 weight percent of a glyme or mixture of glymes and a lithium salt in an amount of from 20 to 85 weight percent, each weight percent based on the total weight of the glyme and lithium salt combined, and a polymeric complexing agent present in an amount of from 5 to 80 percent by weight, based on the total weight of the electrolyte composition.

2 . The composite separator and electrolyte according to claim 1 wherein the porous self-supporting separator film is saturated with a liquid electrolyte composition.

3 . The composite separator and electrolyte according to claim 1 wherein the lithium salt is lithium bis(trifluoromethylsulfonyl)imide (LiTFSI), lithium bis(pentafluoroethylsulfonyl)imide (LiBETI), lithium tris(trifluorosulfonyl)methide, lithium perchlorate (LiClO 4 ), lithium tetrafluoroborate (LiBF 4 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium hexafluorophosphate (LiPF 6 ) or combinations of any of them.

4 . The composite separator and electrolyte according to claim 1 wherein the glyme is tetraethylene glycol dimethyl ether (TEGDME), triethylene glycol dimethyl ether (Triglyme), poly(ethylene glycol dimethyl ether) (PEGDME) (mw: 200-2000), poly(ethylene glycol) (mw: 200-2000), polyglycol methyl ether (mw: 200-2000), ethylene glycol dibutyl ether, or combinations of any of them.

5 . The composite separator and electrolyte according to claim 1 wherein the polymeric complexing agent is PEO.

6 . The composite separator and electrolyte according to claim 1 further comprising inorganic particles.

7 . The composite separator and electrolyte according to claim 1 wherein the lithium salt is present in an amount of from about 24 to about 82 percent by weight, from about 46 to about 66 percent by weight, or from about 40 to about 66 percent by weight, based on the total weight of the glyme and lithium salt combined.

8 . The composite separator and electrolyte according to claim 1 wherein the glyme is present in an amount of from about 15 to about 80 percent by weight, from about 18 to about 76 percent by weight, from about 34 to about 54 percent by weight, or from about 34 to about 60 percent by weight, based on the total weight of the glyme and lithium salt combined.

9 . The composite separator and electrolyte according to claim 1 wherein the polymeric complexing agent is PEO and is present in an amount of from about 10 to about 60 percent by weight, from about 10 to about 50 percent by weight, or about 10 to about 30 percent by weight, based on the total weight of the electrolyte composition.

10 . The composite separator and electrolyte according to claim 1 wherein the at least one electrolyte film is non-aqueous.

11 . The composite separator and electrolyte according to claim 1 wherein the porous self-supporting separator film has a pore size that ranges from greater than 0.015 micrometers to 1 micrometer.

12 . The composite separator and electrolyte according to claim 1 wherein the porous self-supporting separator film is dry.

13 . A solid state battery comprising:
an anode; a cathode; and a composite separator and electrolyte in contact with the anode and cathode, the composite separator and electrolyte comprising a porous self-supporting separator film, the porous self-supporting film having a first major surface and a second major surface; at least one electrolyte film contacting the first major surface of the porous self-supporting film, the at least one electrolyte film comprising from 0 to 80 weight percent of a glyme or mixture of glymes and a lithium salt in an amount of from 20 to 85 weight percent, each weight percent based on the total weight of the glyme and lithium salt combined, and a polymeric complexing agent present in an amount of from 5 to 80 percent by weight, based on the total weight of the electrolyte composition.

14 . The solid state battery according to claim 13 wherein the anode is lithium metal.

15 . The solid state battery according to claim 14 wherein the cathode comprises CFx and SVO.

16 . The solid state battery according to claim 15 wherein the cathode further includes a lithium salt, a glyme or mixture of glymes and polyethylene oxide.

17 . The solid state battery of claim 16 wherein the complexing agent is polyethylene oxide.

18 . The solid state battery of claim 17 wherein the glyme or mixture of glymes is present in an amount of from about 34 to about 54 percent by weight, the lithium salt is present in an amount of from about 40 to about 66 percent by weight and the polyethylene oxide is present in an amount of from about 10 to about 30 percent by weight.

19 . The solid state battery of claim 18 further comprising another electrolyte film contacting the second major surface of the porous self-supporting film, said another electrolyte film having the same composition of said at least one electrolyte film.

20 . The solid state battery of claim 19 wherein the cathode comprises a mixture of CFx, SVO, carbon black and polytetrafluoroethylene in an amount of from 40 to 90 weight percent based on the total weight of the cathode, and a mixture of lithium salt, glyme and polyethylene oxide in an amount of from 5 to 75 weight percent based on the total weight of the cathode.

Assignees

• Medtronic Inc

Inventors

• Ye Hui
• Bomstad Timothy T
• Gomadam Parthasarathy M
• Jain Gaurav
• Nielsen Christian S
• Tamirisa Prabhakar A
• Vanelzen Collette M

Classifications

• H01M6/181

  with polymeric electrolytes · CPC title

• H01M4/583 Primary

  Carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• H01M4/54

  of silver · CPC title

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• H01M10/0568 Primary

  characterised by the solutes · CPC title