Method of improving power density and fast-chargeability of a lithium secondary battery

Patent metadata

Field	Value
Publication number	US-10840565-B2
Application number	US-201816101921-A
Country	US
Kind code	B2
Filing date	Aug 13, 2018
Priority date	Aug 13, 2018
Publication date	Nov 17, 2020
Grant date	Nov 17, 2020

Abstract

Provided is a method of improving fast-dischargeability or high rate capability of a lithium secondary battery containing an anode, a cathode, a porous separator disposed between the anode and the cathode, and an electrolyte, wherein the method comprises packing particles of a cathode active material to form a cathode active material layer having interstitial spaces and disposing a lithium ion receptor in the interstitial spaces, configured to receive lithium ions from the anode through the porous separator when the battery is discharged and to enable the lithium ions to enter the particles of cathode active material in a time-delayed manner.

First claim

The invention claimed is:

1. A method of improving fast-dischargeability of a lithium secondary battery, wherein said battery comprises an anode, a cathode, a porous separator or lithium ion-permeable membrane disposed between said anode and said cathode, and an electrolyte, wherein said method comprises packing particles of a cathode active material to form a cathode active material layer having interstitial spaces and disposing a lithium ion receptor in said interstitial spaces, configured to receive lithium ions from said anode through said porous separator or membrane when said battery is discharged and to enable said lithium ions to enter said particles of cathode active material in a time-delayed manner.

2. The method of claim 1 , wherein said lithium ion receptor comprises lithium-capturing groups dispersed in a fluid residing in said interstitial spaces and said lithium-capturing groups are selected from (a) redox forming species that reversibly form a redox pair with a lithium ion when said battery is charged; (b) electron-donating groups interspaced between non-electron-donating groups; (c) anions and cations wherein the anions are more mobile than the cations; (d) chemical reducing groups that partially reduce lithium ions from Li +1 to Li +δ , wherein 0<δ<1; (e) an ionic liquid; or (f) a combination thereof.

3. The method of claim 2 , wherein said redox pair with lithium is selected from the group consisting of lithium 4-methylbenzenesulfonate, lithium 3,5-dicarboxybenzenesulfonate, lithium 2,6-dimethylbenzene-1,4-disulfonate, 3,3′-((1,2-dithiane-4,5-diyl)bis(oxy))bis(N-hydroxypropanamide), 3,3′-((4-mercapto-1,2-phenylene)bis(oxy))bis(N-hydroxypropanamide), lithium aniline sulfonate, poly(lithium-4-styrenesulfonate), lithium sulfate, lithium phosphate, lithium phosphate monobasic, lithium trifluoromethanesulfonate, lithium 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluorooctane-1-sulfonate, lithium 2,6-di-tert-butylbenzene-1,4-disulfonate, lithium aniline sulfonate, poly(lithium-4-styrenesulfonate, and combinations thereof.

4. The method of claim 2 , wherein said lithium ion-capturing group contains a salt that is dissociated into an anion and a cation in a liquid medium wherein said salt is selected from the group consisting of Li 2 CO 3 , Li 2 O, Li 2 C 2 O 4 , LiOH, LiX, ROCO 2 Li, HCOLi, ROLi, (ROCO 2 Li) 2 , (CH 2 OCO 2 Li) 2 , Li 2 S, Li x SO y , Na 2 CO 3 , Na 2 O, Na 2 C 2 O 4 , NaOH, NaX, ROCO 2 Na, HCONa, RONa, (ROCO 2 Na) 2 , (CH 2 OCO 2 Na) 2 , Na 2 S, Na x SO y , and combinations thereof, wherein X=F, Cl, I, or Br, R=a hydrocarbon group, 0<x≤1 and 1≤y≤4 and wherein said liquid medium to dissolve the salt contains a solvent selected from the group consisting of 1,3-dioxolane (DOL), 1,2-dimethoxyethane (DME), tetraethylene glycol dimethylether (TEGDME), poly(ethylene glycol) dimethyl ether (PEGDME), diethylene glycol dibutyl ether (DEGDBE), 2-ethoxyethyl ether (EEE), sulfone, sulfolane, ethylene carbonate (EC), dimethyl carbonate (DMC), methylethyl carbonate (MEC), diethyl carbonate (DEC), ethyl propionate, methyl propionate, propylene carbonate (PC), gamma-butyrolactone (γ-BL), acetonitrile (AN), ethyl acetate (EA), propyl formate (PF), methyl formate (MF), toluene, xylene, methyl acetate (MA), fluoroethylene carbonate (FEC), vinylene carbonate (VC), allyl ethyl carbonate (AEC), a hydrofluoroether, hydrofluoro ether (HFE), trifluoro propylene carbonate (FPC), methyl nonafluorobutyl ether (MFE), fluoroethylene carbonate (FEC), tris(trimethylsilyl)phosphite (TTSPi), triallyl phosphate (TAP), ethylene sulfate (DTD), 1,3-propane sultone (PS), propene sultone (PES), diethyl carbonate (DEC), alkylsiloxane (Si—O), alkyylsilane (Si—C), liquid oligomeric silaxane (—Si—O—Si—), tetraethylene glycol dimethylether (TEGDME), an ionic liquid solvent, and combinations thereof.

5. The method of claim 2 , wherein said lithium ion-capturing groups contain an ionic liquid having a cation selected from the group consisting of tetra-alkylammonium, di-, tri-, or tetra-alkylimidazolium, alkylpyridinium, dialkyl-pyrrolidinium, dialkylpiperidinium, tetraalkylphosphonium, trialkylsulfonium, and combinations thereof.

6. The method of claim 2 , wherein said lithium ion-capturing groups contain an ionic liquid having an anion selected from the group consisting of BF 4 − , B(CN) 4 − , CH 3 BF 3 − , CH 2 CHBF 3 − , CF 3 BF 3 − , C 2 F 5 BF 3 − , n-C 3 F 7 BF 3 − , n-C 4 F 9 BF 3 − , PF 6 − , CF 3 CO 2 − , CF 3 SO 3 − , N(SO 2 CF 3 ) 2 − , N(COCF 3 )(SO 2 CF 3 ) − , N(SO 2 F) 2 − , N(CN) 2 − , C(CN) 3 − , SCN − , SeCN − , CuCl 2 − , AlCl 4 − , F(HF) 2.3 − , and combinations thereof.

7. The method of claim 2 , wherein said lithium ion-capturing groups comprises an ionic liquid having a 1-ethyl-3-methylimidazolium (EMI) cation and an N,N-bis(trifluoromethane)sulfonamide (TFSI) anion.

8. The method of claim 1 , further comprising a procedure of packing particles of an anode active material to form an anode active material layer having interstitial spaces and disposing a lithium ion reservoir in said interstitial spaces, configured to receive lithium ions from said cathode through said porous separator when said battery is charged and to enable said lithium ions to enter said particles of anode active material in a time-delayed manner.

9. The method of claim 1 , wherein said interstitial spaces occupy a volume fraction of said cathode active material layer from 20% to 75% or the lithium ion capturing groups occupy from 5% to 60% by volume of the cathode active material layer.

10. The method of claim 1 , wherein said cathode active material layer contains no resin binder that bonds the particles of cathode active material together.

11. The method of claim 1 , wherein said step of packing comprises providing an electrically conductive porous layer having pores and impregnating said particles of cathode active material and said lithium ion receptor into said pores of electrically conductive porous layer, wherein cathode active material particles are packed to form interstitial spaces to accommodate said lithium ion receptor therein.

12. The method of claim 11 , wherein said electrically conductive porous layer is selected from the group consisting of metal foam, metal web or screen, perforated metal sheet-based structure, metal fiber mat, metal nanowire mat, conductive polymer nanofiber mat, conductive polymer foam, conductive polymer-coated fiber foam, carbon foam, graphite foam, carbon aerogel, carbon xerogel, graphene foam, graphene oxide foam, reduced graphene oxide foam, carbon fiber foam, graphite fiber foam, exfoliated graphite foam, and combinations thereof.

13. The method of claim 1 , wherein the lithium-capturing group is selected from a molecule having a core or backbone structure and at least a side group that contains an ionic or electron rich group; wherein the core or backbone structure comprises an aryl, heterocycloalkyl, crown etheryl, cyclamyl, cyclenyl, 1,4,7-triazacyclononayl, hexacyclenyl, cryptandyl, naphtalenyl, antracenyl, phenantrenyl, tetracenyl, chrysenyl, tryphenylenyl, pyrenyl, pentacenyl, single-benzene or cyclic structure, double-benzene or bi-cyclic structure, or multiple-cyclic structure having 3-10 benzene rings and wherein the side group comprises CO 2 H, CO 2 M 1 , CO 2 R, SO 3 H, SO 3 M 1 , PO 3 H 2 , PO 3 M 1 2 , PO 3 M 1 H, PO 4 H 2 , PO 4 M 1 2 , PO 4 M 1 H, PO 4 M 2 , C(O)NHOH, NH 2 , NHR, N(R) 2 , NO 2 , COOR, CHO, CH 2 OH, OH, OR, SH, SR, C(O)N(R) 2 , C(O)NHR, C(O)NH 2 , halide, tosylate, mesylate, SO 2 NHR, triflate, isocyanate, cyanate, thiocyanate, isothiocyanate, R, cyano, CF 3 , or Si(OR) 3 ; wherein R is independen

Assignees

• Global Graphene Group Inc

Inventors

• Zhamu Aruna
• Jang Bor Z

Classifications

• H01M50/40

  Separators; Membranes; Diaphragms; Spacing elements inside cells · CPC title

• H01M4/364 Primary

  as mixtures · CPC title

• H01M4/625

  Carbon or graphite · CPC title

• H01M4/62

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

• Y02E60/10

  Energy storage using batteries · CPC title