Polymer binder for lithium battery and method of manufacturing

Abstract

Provided is an anode active material layer for a lithium battery. The anode active material layer comprises multiple anode active material particles and an optional conductive additive that are bonded together by a binder comprising a high-elasticity polymer having a recoverable or elastic tensile strain no less than 10% when measured without an additive or reinforcement in the polymer and a lithium ion conductivity no less than 10−5 S/cm at room temperature. The anode active material preferably has a specific lithium storage capacity greater than 372 mAh/g (e.g. Si, Ge, Sn, SnO2, Co3O4, etc.).

1 .- 27 . (canceled) 
     
     
         28 . A method of manufacturing a lithium battery, said method comprising:
 (a) providing a cathode active material layer and an optional cathode current collector to support said cathode active material layer;   (b) providing an anode active material layer and an optional anode current collector to support said anode active material layer; and   (c) providing an electrolyte in contact with the anode active material layer and the cathode active material layer and an optional separator electrically separating the anode and the cathode;   wherein the operation of providing the anode active material layer includes bonding multiple particles of an anode active material and an optional conductive additive together to form said layer by a binder resin containing a high-elasticity polymer having a recoverable tensile strain from 5% to 700% when measured without an additive or reinforcement and a lithium ion conductivity no less than 10 −5  S/cm at room temperature.   
     
     
         29 . A method of manufacturing a lithium battery, said method comprising:
 (a) providing a cathode active material layer and an optional cathode current collector to support said cathode active material layer;   (b) providing an anode active material layer and an optional anode current collector to support said anode active material layer; and   (c) providing an electrolyte in contact with the anode active material layer and the cathode active material layer and an optional porous separator electrically separating the anode and the cathode;   wherein the operation of providing the anode active material layer includes bonding multiple particles of an anode active material and an optional conductive additive together by a binder resin to form said anode active material layer and applying a thin film of a high-elasticity polymer to cover and protect said anode active material layer, wherein said high-elasticity polymer has a recoverable or elastic tensile strain from 5% to 700% when measured without an additive or reinforcement and a lithium ion conductivity no less than 10 −5  S/cm at room temperature and said thin film has a thickness from 1 nm to 10 μm.   
     
     
         30 . The method of  claim 29 , wherein said thin film of high-elasticity polymer is implemented between said anode active material layer and said porous separator. 
     
     
         31 . The method of  claim 28 , wherein said high-elasticity polymer has a lithium ion conductivity from 1×10 −5  S/cm to 2×10 −2  S/cm. 
     
     
         32 . The method of  claim 28 , wherein said high-elasticity polymer has a recoverable tensile strain from 10% to 300%. 
     
     
         33 . The method of  claim 28 , wherein said high-elasticity polymer contains a cross-linked network polymer chains having an ether linkage, nitrile-derived linkage, benzo peroxide-derived linkage, ethylene oxide linkage, propylene oxide linkage, vinyl alcohol linkage, cyano-resin linkage, triacrylate monomer-derived linkage, tetraacrylate monomer-derived linkage, or a combination thereof in said cross-linked network of polymer chains. 
     
     
         34 . The method of  claim 28 , wherein said high-elasticity polymer contains a cross-linked network of polymer chains selected from nitrile-containing polyvinyl alcohol chains, cyanoresin chains, pentaerythritol tetraacrylate chains, pentaerythritol triacrylate chains, ethoxylated trimethylolpropane triacrylate (ETPTA) chains, ethylene glycol methyl ether acrylate (EGMEA) chains, or a combination thereof. 
     
     
         35 . The method of  claim 28 , wherein said high-elasticity polymer forms a mixture with an elastomer, an electronically conductive polymer, a lithium-ion conducting material, a reinforcement material, or a combination thereof. 
     
     
         36 . The method of  claim 35 , wherein said lithium ion-conducting material is dispersed in said high-elasticity polymer and is selected from 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 , or a combination thereof, wherein X═F, Cl, I, or Br, R=a hydrocarbon group, x=0-1, y=1-4. 
     
     
         37 . The method of  claim 35 , wherein said lithium ion-conducting material is dispersed in said high-elasticity polymer and is selected from lithium perchlorate, LiClO 4 , lithium hexafluorophosphate, LiPF 6 , lithium borofluoride, LiBF 4 , lithium hexafluoroarsenide, LiAsF 6 , lithium trifluoro-metasulfonate, LiCF 3 SO 3 , bis-trifluoromethyl sulfonylimide lithium, LiN(CF 3 SO 2 ) 2 , lithium bis(oxalato)borate, LiBOB, lithium oxalyldifluoroborate, LiBF 2 C 2 O 4 , lithium oxalyldifluoroborate, LiBF 2 C 2 O 4 , lithium nitrate, LiNO 3 , Li-Fluoroalkyl-Phosphates, LiPF 3 (CF 2 CF 3 ) 3 , lithium bisperfluoro-ethysulfonylimide, LiBETI, lithium bis(trifluoromethanesulphonyl)imide, lithium bis(fluorosulphonyl)imide, lithium trifluoromethanesulfonimide, LiTFSI, an ionic liquid-based lithium salt, or a combination thereof. 
     
     
         38 . The method of  claim 28 , wherein said anode active material is selected from the group consisting of: (a) silicon (Si), germanium (Ge), tin (Sn), zinc (Zn), aluminum (Al), titanium (Ti), nickel (Ni), cobalt (Co), and cadmium (Cd); (b) oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Fe, Ni, Co, V, or Cd, and their mixtures, composites, or lithium-containing composites; (c) lithium titanate, lithium manganate, lithium aluminate, lithium-containing titanium oxide, lithium transition metal oxide, ZnCo 2 O 4 ; (d) prelithiated versions thereof; (e) mixtures thereof with a carbon, graphene, or graphite material; (f) particles of Li, Li alloy, or surface-stabilized Li having at least 60% by weight of lithium element therein; and (f) combinations thereof. 
     
     
         39 . The method of  claim 28 , wherein said one or a plurality of anode active material particles is coated with a layer of carbon or graphene. 
     
     
         40 . The method of  claim 28 , wherein said one or a plurality of anode active material particles is mixed with a carbon, graphene, or graphite material to form a mixture and said mixture is embraced by one or a plurality of graphene sheets. 
     
     
         41 . The method of  claim 29 , wherein said one or plurality of anode active material particles are mixed with a carbon material, a graphite material, and/or graphene sheets to form a mixture that is embraced by external graphene sheets to form graphene-embraced anode active material particulates, which are then bonded by the binder resin.